WIP

From https://github.com/zrepl/zrepl/issues/691

The last_n prune rule keeps everything, regardless of if it matches the
regex or not, if there are less than count snapshot. The expectation
would be to never keep non-regex snapshots, regardless of number.

.circleci/config.yml

@@ -1,5 +1,8 @@
 version: 2.1
-
+orbs:
+  # NB: 1.7.2 is not the Go version, but the Orb version
+  # https://circleci.com/developer/orbs/orb/circleci/go#usage-go-modules-cache
+  go: circleci/go@1.7.2
 commands:
   setup-home-local-bin:
     steps:
@@ -24,18 +27,12 @@ commands:
 
   apt-update-and-install-common-deps:
     steps:
-      - run: sudo apt update && sudo apt install gawk make
-
-  restore-cache-gomod:
-    steps:
-      - restore_cache:
-          key: go-mod-v4-{{ checksum "go.sum" }}
-  save-cache-gomod:
-    steps:
-      - save_cache:
-          key: go-mod-v4-{{ checksum "go.sum" }}
-          paths:
-            - "/go/pkg/mod"
+      - run: sudo apt-get update
+      - run: sudo apt-get install -y gawk make
+      # CircleCI doesn't update its cimg/go images.
+      # So, need to update manually to get up-to-date trust chains.
+      # The need for this was required for cimg/go:1.12, but let's future proof this here and now.
+      - run: sudo apt-get install -y git ca-certificates
 
   install-godep:
     steps:
@@ -50,94 +47,48 @@ commands:
       - invoke-lazy-sh:
           subcommand: docdep
 
-  download-and-install-minio-client:
-    steps:
-      - setup-home-local-bin
-      - restore_cache:
-          key: minio-client-v2
-      - run:
-          shell: /bin/bash -eo pipefail
-          command: |
-            if which mc; then exit 0; fi
-            sudo curl -sSL https://dl.min.io/client/mc/release/linux-amd64/archive/mc.RELEASE.2020-08-20T00-23-01Z \
-              -o "$HOME/.local/bin/mc"
-            sudo chmod +x "$HOME/.local/bin/mc"
-      - save_cache:
-          key: minio-client-v2
-          paths:
-            - "$HOME/.local/bin/mc"
-
-  upload-minio:
+  docs-publish-sh:
     parameters:
-      src:
-        type: string
-      dst:
-        type: string
+      push:
+        type: boolean
     steps:
+      - checkout
       - run:
-          shell: /bin/bash -eo pipefail
-          when: always
           command: |
-            if [ -n "$CIRCLE_PR_NUMBER" ]; then # CIRCLE_PR_NUMBER is guaranteed to be only present in forked PRs (external)
-              echo "Forked PR detected. Sry, can't trust you with credentials to external artifact store, use CircleCI's instead."
-              exit 0
-            fi
-            set -u # from now on
+            git config --global user.email "zreplbot@cschwarz.com"
+            git config --global user.name "zrepl-github-io-ci"
 
-            mc config host add --api s3v4 zrepl-minio https://minio.cschwarz.com ${MINIO_ACCESS_KEY} ${MINIO_SECRET_KEY}
+      # if we're pushing, we need to add the deploy key
+      # which is stored as "Additional SSH Keys" in the CircleCI project settings.
+      # We can't use the CircleCI-manage deploy key because we're pushing
+      # to a different repo than the one we're building.
+      - when:
+          condition: << parameters.push >>
+          steps:
+            # https://circleci.com/docs/2.0/add-ssh-key/#adding-multiple-keys-with-blank-hostnames
+            - run: ssh-add -D
+            # the default circleci ssh config only additional ssh keys for Host !github.com
+            - run:
+                command: |
+                  cat > ~/.ssh/config \<<EOF
+                  Host *
+                    IdentityFile /home/circleci/.ssh/id_rsa_458e62c517f6c480e40452126ce47421
+                  EOF
+            - add_ssh_keys:
+                fingerprints:
+                  # deploy key for zrepl.github.io
+                  - "45:8e:62:c5:17:f6:c4:80:e4:04:52:12:6c:e4:74:21"
 
-            # keep in sync with set-github-minio-status
-            jobprefix=zrepl-ci-artifacts/${CIRCLE_SHA1}-pipeline-<<pipeline.number>>/${CIRCLE_JOB}
-
-            # Upload artifacts
-            mkdir -p ./artifacts
-            mc cp -r <<parameters.src>> "zrepl-minio/$jobprefix/<<parameters.dst>>"
-
-  set-github-minio-status:
-    parameters:
-      context:
-        type: string
-      description:
-        type: string
-      minio-dst:
-        type: string
-    steps:
-      - run:
-          shell: /bin/bash -eo pipefail
-          command: |
-            if [ -n "$CIRCLE_PR_NUMBER" ]; then # CIRCLE_PR_NUMBER is guaranteed to be only present in forked PRs (external)
-              echo "Forked PR detected. Sry, can't trust you with credentials to external artifact store, use CircleCI's instead."
-              exit 0
-            fi
-            set -u # from now on
-
-            # keep in sync with with upload-minio command
-            jobprefix=zrepl-ci-artifacts/${CIRCLE_SHA1}-pipeline-<<pipeline.number>>/${CIRCLE_JOB}
-            # Push Artifact Link to GitHub
-            REPO="zrepl/zrepl"
-            COMMIT="${CIRCLE_SHA1}"
-            JOB_NAME="${CIRCLE_JOB}"
-            CONTEXT="<<parameters.context>>"
-            DESCRIPTION="<<parameters.description>>"
-            TARGETURL=https://minio.cschwarz.com/minio/"$jobprefix"/"<<parameters.minio-dst>>"
-            curl "https://api.github.com/repos/$REPO/statuses/$COMMIT" \
-              -H "Content-Type: application/json" \
-              -H "Authorization: token $GITHUB_COMMIT_STATUS_TOKEN" \
-              -X POST \
-              -d '{"context":"'"$CONTEXT"'", "state": "success", "description":"'"$DESCRIPTION"'", "target_url":"'"$TARGETURL"'"}'
-
-
-  trigger-pipeline:
-    parameters:
-      body_no_shell_subst:
-        type: string
-    steps:
-      - run: |
-          curl -X POST https://circleci.com/api/v2/project/github/zrepl/zrepl/pipeline \
-            -H 'Content-Type: application/json' \
-            -H 'Accept: application/json' \
-            -H "Circle-Token: $ZREPL_BOT_CIRCLE_TOKEN" \
-            --data '<<parameters.body_no_shell_subst>>'
+      # caller must install-docdep
+      - when:
+          condition: << parameters.push >>
+          steps:
+            - run: bash -x docs/publish.sh -c -a -P
+      - when:
+          condition:
+            not: << parameters.push >>
+          steps:
+            - run: bash -x docs/publish.sh -c -a
 
 parameters:
   do_ci:
@@ -150,7 +101,7 @@ parameters:
 
   release_docker_baseimage_tag:
     type: string
-    default: "1.16"
+    default: "1.21"
 
 workflows:
   version: 2
@@ -160,19 +111,19 @@ workflows:
     jobs:
       - quickcheck-docs
       - quickcheck-go: &quickcheck-go-smoketest
-          name: quickcheck-go-amd64-linux-1.16
-          goversion: &latest-go-release "1.16"
+          name: quickcheck-go-amd64-linux-1.21
+          goversion: &latest-go-release "1.21"
           goos: linux
           goarch: amd64
       - test-go-on-latest-go-release:
           goversion: *latest-go-release
       - quickcheck-go:
           requires:
-            - quickcheck-go-amd64-linux-1.16 #quickcheck-go-smoketest.name
+            - quickcheck-go-amd64-linux-1.21 #quickcheck-go-smoketest.name
           matrix: &quickcheck-go-matrix
             alias: quickcheck-go-matrix
             parameters:
-              goversion: [*latest-go-release, "1.12"]
+              goversion: [*latest-go-release, "1.20"]
               goos: ["linux", "freebsd"]
               goarch: ["amd64", "arm64"]
             exclude:
@@ -180,10 +131,14 @@ workflows:
               - goversion: *latest-go-release
                 goos: linux
                 goarch: amd64
-              # not supported by Go 1.12
-              - goversion: "1.12"
-                goos: freebsd
-                goarch: arm64
+      - platformtest:
+          matrix:
+            parameters:
+              goversion: [*latest-go-release]
+              goos: ["linux"]
+              goarch: ["amd64"]
+          requires:
+            - quickcheck-go-<< matrix.goarch >>-<< matrix.goos >>-<< matrix.goversion >>
 
   release:
     when: << pipeline.parameters.do_release >>
@@ -201,20 +156,7 @@ workflows:
             - release-deb
             - release-rpm
 
-  periodic:
-    triggers:
-      - schedule:
-          cron: "00 17 * * *"
-          filters:
-            branches:
-              only:
-                - master
-                - stable
-                - problame/circleci-build
-    jobs:
-      - periodic-full-pipeline-run
-
-  zrepl.github.io:
+  publish-zrepl.github.io:
     jobs:
       - publish-zrepl-github-io:
           filters:
@@ -225,22 +167,15 @@ workflows:
 jobs:
   quickcheck-docs:
     docker:
-      - image: cimg/base:2020.08
+      - image: cimg/base:2023.09
     steps:
       - checkout
       - install-docdep
+      # do the current docs build
       - run: make docs
-
-      - store_artifacts:
-          path: artifacts
-      - download-and-install-minio-client
-      - upload-minio:
-          src: artifacts
-          dst: ""
-      - set-github-minio-status:
-          context: artifacts/${CIRCLE_JOB}
-          description: artifacts of CI job ${CIRCLE_JOB}
-          minio-dst: ""
+      # does the publish.sh script still work?
+      - docs-publish-sh:
+          push: false
 
   quickcheck-go:
     parameters:
@@ -251,7 +186,7 @@ jobs:
       goarch:
         type: string
     docker:
-      - image: circleci/golang:<<parameters.goversion>>
+      - image: cimg/go:<<parameters.goversion>>
     environment:
       GOOS: <<parameters.goos>>
       GOARCH: <<parameters.goarch>>
@@ -259,44 +194,66 @@ jobs:
     steps:
       - checkout
 
-      - restore-cache-gomod
+      - go/load-cache:
+          key: quickcheck-<<parameters.goversion>>
+      - install-godep
       - run: go mod download
       - run: cd build && go mod download
-      - save-cache-gomod
+      - go/save-cache:
+          key: quickcheck-<<parameters.goversion>>
 
-      - install-godep
       - run: make formatcheck
       - run: make generate-platform-test-list
       - run: make zrepl-bin test-platform-bin
       - run: make vet
       - run: make lint
 
-      - download-and-install-minio-client
       - run: rm -f artifacts/generate-platform-test-list
       - store_artifacts:
           path: artifacts
-      - upload-minio:
-          src: artifacts
-          dst: ""
-      - set-github-minio-status:
-          context: artifacts/${CIRCLE_JOB}
-          description: artifacts of CI job ${CIRCLE_JOB}
-          minio-dst: ""
+      - persist_to_workspace:
+          root: .
+          paths: [.]
+
+  platformtest:
+    parameters:
+      goversion:
+        type: string
+      goos:
+        type: string
+      goarch:
+        type: string
+    machine:
+      image: ubuntu-2204:current
+    resource_class: medium
+    environment:
+      GOOS: <<parameters.goos>>
+      GOARCH: <<parameters.goarch>>
+    steps:
+      - attach_workspace:
+          at: .
+      - run: sudo apt-get update
+      - run: sudo apt-get install -y zfsutils-linux
+      - run: sudo zfs version
+      - run: sudo make test-platform GOOS="$GOOS" GOARCH="$GOARCH"
 
   test-go-on-latest-go-release:
     parameters:
       goversion:
         type: string
     docker:
-      - image: circleci/golang:<<parameters.goversion>>
+      - image: cimg/go:<<parameters.goversion>>
     steps:
       - checkout
-      - restore-cache-gomod
+      - go/load-cache:
+          key: make-test-go
       - run: make test-go
-      # don't save-cache-gomod here, test-go doesn't pull all the dependencies
+      - go/save-cache:
+          key: make-test-go
 
   release-build:
-    machine: true
+    machine:
+      image: ubuntu-2004:202201-02
     steps:
       - checkout
       - run: make release-docker RELEASE_DOCKER_BASEIMAGE_TAG=<<pipeline.parameters.release_docker_baseimage_tag>>
@@ -304,7 +261,8 @@ jobs:
           root: .
           paths: [.]
   release-deb:
-    machine: true
+    machine:
+      image: ubuntu-2004:202201-02
     steps:
       - attach_workspace:
           at: .
@@ -315,7 +273,8 @@ jobs:
             - "artifacts/*.deb"
 
   release-rpm:
-    machine: true
+    machine:
+      image: ubuntu-2004:202201-02
     steps:
       - attach_workspace:
           at: .
@@ -331,48 +290,15 @@ jobs:
     steps:
       - attach_workspace:
           at: .
+      - run: make wrapup-and-checksum
       - store_artifacts:
           path: artifacts
-      - download-and-install-minio-client
-      - upload-minio:
-          src: artifacts
-          dst: ""
-      - set-github-minio-status:
-          context: artifacts/release
-          description: CI-generated release artifacts
-          minio-dst: ""
-
-  periodic-full-pipeline-run:
-    docker:
-      - image: cimg/base:2020.08
-    steps:
-      - trigger-pipeline:
-          body_no_shell_subst: '{"branch":"<<pipeline.git.branch>>", "parameters": { "do_ci": true, "do_release": true }}'
 
   publish-zrepl-github-io:
     docker:
-      - image: cimg/python:3.7
+      - image: cimg/base:2023.09
     steps:
       - checkout
-      - invoke-lazy-sh:
-          subcommand: docdep
-      - run:
-          command: |
-            git config --global user.email "me@cschwarz.com"
-            git config --global user.name "zrepl-github-io-ci"
-
-      # https://circleci.com/docs/2.0/add-ssh-key/#adding-multiple-keys-with-blank-hostnames
-      - run: ssh-add -D
-      # the default circleci ssh config only additional ssh keys for Host !github.com
-      - run:
-          command: |
-            cat > ~/.ssh/config \<<EOF
-            Host *
-              IdentityFile /home/circleci/.ssh/id_rsa_458e62c517f6c480e40452126ce47421
-            EOF
-      - add_ssh_keys:
-          fingerprints:
-            # deploy key for zrepl.github.io
-            - "45:8e:62:c5:17:f6:c4:80:e4:04:52:12:6c:e4:74:21"
-
-      - run: bash -x docs/publish.sh -c -a
+      - install-docdep
+      - docs-publish-sh:
+          push: true

.circleci/download_artifacts.py

@@ -0,0 +1,84 @@
+import argparse
+from pathlib import Path
+import re
+
+import requests
+
+import time
+
+import os
+import argparse
+from pathlib import Path
+
+
+circle_token = os.environ.get('CIRCLE_TOKEN')
+if not circle_token:
+    raise ValueError('CIRCLE_TOKEN environment variable not set')
+
+parser = argparse.ArgumentParser(description='Download artifacts from CircleCI')
+parser.add_argument('build_num', type=str, help='Build number')
+parser.add_argument('dst', type=Path, help='Destination directory')
+parser.add_argument('--prefix', type=str, default='', help='Filter for prefix')
+parser.add_argument('--match', type=str, default='.*', help='Only include paths matching the given regex')
+
+args = parser.parse_args()
+
+res = requests.get(
+    f"https://circleci.com/api/v1.1/project/github/zrepl/zrepl/{args.build_num}/artifacts",
+    headers={
+        "Circle-Token": circle_token,
+    },
+)
+res.raise_for_status()
+
+# https://circleci.com/docs/api/v1/index.html#artifacts-of-a-job
+# [ {
+#   "path" : "raw-test-output/go-test-report.xml",
+#   "pretty_path" : "raw-test-output/go-test-report.xml",
+#   "node_index" : 0,
+#   "url" : "https://24-88881093-gh.circle-artifacts.com/0/raw-test-output/go-test-report.xml"
+# }, {
+#   "path" : "raw-test-output/go-test.out",
+#   "pretty_path" : "raw-test-output/go-test.out",
+#   "node_index" : 0,
+#   "url" : "https://24-88881093-gh.circle-artifacts.com/0/raw-test-output/go-test.out"
+# } ]
+res = res.json()
+
+for artifact in res:
+    if not artifact["pretty_path"].startswith(args.prefix):
+        continue
+    if not re.match(args.match, artifact["pretty_path"]):
+        continue
+    stripped = artifact["pretty_path"][len(args.prefix):]
+    print(f"Downloading {artifact['pretty_path']} to {args.dst / stripped}")
+    artifact_rel = Path(stripped)
+    artifact_dst = args.dst / artifact_rel
+    artifact_dst.parent.mkdir(parents=True, exist_ok=True)
+
+    res = requests.get(
+        artifact["url"],
+        headers={
+            "Circle-Token": circle_token,
+        },
+        stream=True,
+    )
+    res.raise_for_status()
+
+    total_size = int(res.headers.get("Content-Length", 0))
+    block_size = 128 * 1024
+    with open(artifact_dst, "wb") as f:
+        progress = 0
+        start_time = time.time()
+        for chunk in res.iter_content(chunk_size=block_size):
+            f.write(chunk)
+            progress += len(chunk)
+            percent = progress / total_size * 100
+            elapsed_time = time.time() - start_time
+            if elapsed_time >= 5:
+                print(f"Downloaded {progress}/{total_size} bytes ({percent:.2f}%)", end="\r")
+                start_time = time.time()
+        print(f"Downloaded {progress}/{total_size} bytes ({percent:.2f}%)")
+    print("Download complete!")
+
+print("All files downloaded")

.golangci.yml

@@ -7,4 +7,10 @@ issues:
     - path: _test\.go
       linters:
         - errcheck
+    # Disable staticcheck 'Empty body in an if or else branch' as it's useful
+    # to put a comment into an empty else-clause that explains why whatever
+    # is done in the if-caluse is not necessary if the condition is false.
+    - linters:
+        - staticcheck
+      text: "SA9003:"
 

Makefile

@@ -1,5 +1,5 @@
 .PHONY: generate build test vet cover release docs docs-clean clean format lint platformtest
-.PHONY: release bins-all release-noarch
+.PHONY: release release-noarch
 .DEFAULT_GOAL := zrepl-bin
 
 ARTIFACTDIR := artifacts
@@ -14,13 +14,15 @@ ifndef _ZREPL_VERSION
     endif
 endif
 
+ZREPL_PACKAGE_RELEASE := 1
+
 GO := go
 GOOS ?= $(shell bash -c 'source <($(GO) env) && echo "$$GOOS"')
 GOARCH ?= $(shell bash -c 'source <($(GO) env) && echo "$$GOARCH"')
 GOARM ?= $(shell bash -c 'source <($(GO) env) && echo "$$GOARM"')
 GOHOSTOS ?= $(shell bash -c 'source <($(GO) env) && echo "$$GOHOSTOS"')
 GOHOSTARCH ?= $(shell bash -c 'source <($(GO) env) && echo "$$GOHOSTARCH"')
-GO_ENV_VARS := GO111MODULE=on
+GO_ENV_VARS := GO111MODULE=on CGO_ENABLED=0
 GO_LDFLAGS := "-X github.com/zrepl/zrepl/version.zreplVersion=$(_ZREPL_VERSION)"
 GO_MOD_READONLY := -mod=readonly
 GO_EXTRA_BUILDFLAGS :=
@@ -28,7 +30,7 @@ GO_BUILDFLAGS := $(GO_MOD_READONLY) $(GO_EXTRA_BUILDFLAGS)
 GO_BUILD := $(GO_ENV_VARS) $(GO) build $(GO_BUILDFLAGS) -ldflags $(GO_LDFLAGS)
 GOLANGCI_LINT := golangci-lint
 GOCOVMERGE := gocovmerge
-RELEASE_DOCKER_BASEIMAGE_TAG ?= 1.16
+RELEASE_DOCKER_BASEIMAGE_TAG ?= 1.21
 RELEASE_DOCKER_BASEIMAGE ?= golang:$(RELEASE_DOCKER_BASEIMAGE_TAG)
 
 ifneq ($(GOARM),)
@@ -50,21 +52,20 @@ printvars:
 release: clean
 	# no cross-platform support for target test
 	$(MAKE) test-go
-	$(MAKE) bins-all
+	$(MAKE) _run_make_foreach_target_tuple RUN_MAKE_FOREACH_TARGET_TUPLE_ARG="vet"
+	$(MAKE) _run_make_foreach_target_tuple RUN_MAKE_FOREACH_TARGET_TUPLE_ARG="lint"
+	$(MAKE) _run_make_foreach_target_tuple RUN_MAKE_FOREACH_TARGET_TUPLE_ARG="zrepl-bin"
+	$(MAKE) _run_make_foreach_target_tuple RUN_MAKE_FOREACH_TARGET_TUPLE_ARG="test-platform-bin"
 	$(MAKE) noarch
-	$(MAKE) wrapup-and-checksum
-	$(MAKE) check-git-clean
-ifeq (SIGN, 1)
-	$(make) sign
-endif
-	@echo "ZREPL RELEASE ARTIFACTS AVAILABLE IN artifacts/release"
 
 release-docker: $(ARTIFACTDIR)
 	sed 's/FROM.*!SUBSTITUTED_BY_MAKEFILE/FROM $(RELEASE_DOCKER_BASEIMAGE)/' build.Dockerfile > artifacts/release-docker.Dockerfile
 	docker build -t zrepl_release --pull -f artifacts/release-docker.Dockerfile .
 	docker run --rm -i -v $(CURDIR):/src -u $$(id -u):$$(id -g) \
 		zrepl_release \
-		make release GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM)
+		make release \
+			GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM) \
+			ZREPL_VERSION=$(ZREPL_VERSION) ZREPL_PACKAGE_RELEASE=$(ZREPL_PACKAGE_RELEASE)
 
 debs-docker:
 	$(MAKE) _debs_or_rpms_docker _DEB_OR_RPM=deb
@@ -81,9 +82,14 @@ rpm: $(ARTIFACTDIR) # artifacts/_zrepl.zsh_completion artifacts/bash_completion
 	$(eval _ZREPL_RPM_TOPDIR_ABS := $(CURDIR)/$(ARTIFACTDIR)/rpmbuild)
 	rm -rf "$(_ZREPL_RPM_TOPDIR_ABS)"
 	mkdir "$(_ZREPL_RPM_TOPDIR_ABS)"
-	mkdir -p "$(_ZREPL_RPM_TOPDIR_ABS)"/{SPECS,RPMS,BUILD,BUILDROOT}
-	sed "s/^Version:.*/Version:          $(_ZREPL_RPM_VERSION)/g" \
-	    packaging/rpm/zrepl.spec >  $(_ZREPL_RPM_TOPDIR_ABS)/SPECS/zrepl.spec
+	for d in BUILD BUILDROOT RPMS SOURCES SPECS SRPMS; do \
+		mkdir -p "$(_ZREPL_RPM_TOPDIR_ABS)/$$d"; \
+	done
+	sed \
+		-e "s/^Version:.*/Version:          $(_ZREPL_RPM_VERSION)/g" \
+		-e "s/^Release:.*/Release:          $(ZREPL_PACKAGE_RELEASE)/g" \
+	    packaging/rpm/zrepl.spec \
+		>  $(_ZREPL_RPM_TOPDIR_ABS)/SPECS/zrepl.spec
 
 	# see /usr/lib/rpm/platform
 ifeq ($(GOARCH),amd64)
@@ -110,13 +116,16 @@ rpm-docker:
 	docker build -t zrepl_rpm_pkg --pull -f packaging/rpm/Dockerfile .
 	docker run --rm -i -v $(CURDIR):/build/src -u $$(id -u):$$(id -g) \
 		zrepl_rpm_pkg \
-		make rpm GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM)
+		make rpm \
+			GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM) \
+			ZREPL_VERSION=$(ZREPL_VERSION) ZREPL_PACKAGE_RELEASE=$(ZREPL_PACKAGE_RELEASE)
+
 
 deb: $(ARTIFACTDIR) # artifacts/_zrepl.zsh_completion artifacts/bash_completion docs zrepl-bin
 
 	cp packaging/deb/debian/changelog.template packaging/deb/debian/changelog
 	sed -i 's/DATE_DASH_R_OUTPUT/$(shell date -R)/' packaging/deb/debian/changelog
-	VERSION="$(subst -,.,$(_ZREPL_VERSION))"; \
+	VERSION="$(subst -,.,$(_ZREPL_VERSION))-$(ZREPL_PACKAGE_RELEASE)"; \
 		export VERSION="$${VERSION#v}"; \
 		sed -i 's/VERSION/'"$$VERSION"'/' packaging/deb/debian/changelog
 
@@ -134,11 +143,19 @@ endif
 
 deb-docker:
 	docker build -t zrepl_debian_pkg --pull -f packaging/deb/Dockerfile .
+	# Use a small open file limit to make fakeroot work. If we don't
+	# specify it, docker daemon will use its file limit. I don't know
+	# what changed (Docker, its systemd service, its Go version). But I
+	# observed fakeroot iterating close(i) up to i > 1000000, which costs
+	# a good amount of CPU time and makes the build slow.
 	docker run --rm -i -v $(CURDIR):/build/src -u $$(id -u):$$(id -g) \
+		--ulimit nofile=1024:1024 \
 		zrepl_debian_pkg \
-		make deb GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM)
+		make deb \
+			GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM) \
+			ZREPL_VERSION=$(ZREPL_VERSION) ZREPL_PACKAGE_RELEASE=$(ZREPL_PACKAGE_RELEASE)
 
-# expects `release` target to have run before
+# expects `release`, `deb` & `rpm` targets to have run before
 NOARCH_TARBALL := $(ARTIFACTDIR)/zrepl-noarch.tar
 wrapup-and-checksum:
 	rm -f $(NOARCH_TARBALL)
@@ -155,7 +172,7 @@ wrapup-and-checksum:
 		config/samples
 	rm -rf "$(ARTIFACTDIR)/release"
 	mkdir -p "$(ARTIFACTDIR)/release"
-	cp -l $(ARTIFACTDIR)/zrepl-* \
+	cp -l $(ARTIFACTDIR)/zrepl* \
 		$(ARTIFACTDIR)/platformtest-* \
 		"$(ARTIFACTDIR)/release"
 	cd "$(ARTIFACTDIR)/release" && sha512sum $$(ls | sort) > sha512sum.txt
@@ -173,35 +190,44 @@ check-git-clean:
 		fi; \
 	fi;
 
+tag-release:
+	test -n "$(ZREPL_TAG_VERSION)" || exit 1
+	git tag -u '328A6627FA98061D!' -m "$(ZREPL_TAG_VERSION)" "$(ZREPL_TAG_VERSION)"
+
 sign:
-	gpg -u "89BC 5D89 C845 568B F578  B306 CDBD 8EC8 E27C A5FC" \
+	gpg -u '328A6627FA98061D!' \
 		--armor \
 		--detach-sign $(ARTIFACTDIR)/release/sha512sum.txt
 
 clean: docs-clean
 	rm -rf "$(ARTIFACTDIR)"
 
-##################### BINARIES #####################
-.PHONY: bins-all lint test-go test-platform cover-merge cover-html vet zrepl-bin test-platform-bin generate-platform-test-list
+download-circleci-release:
+	rm -rf "$(ARTIFACTDIR)"
+	mkdir -p "$(ARTIFACTDIR)/release"
+	python3 .circleci/download_artifacts.py --prefix 'artifacts/release/' "$(BUILD_NUM)" "$(ARTIFACTDIR)/release"
 
-BINS_ALL_TARGETS := zrepl-bin test-platform-bin vet lint
-GO_SUPPORTS_ILLUMOS := $(shell $(GO) version | gawk -F '.' '/^go version /{split($$0, comps, " "); split(comps[3], v, "."); if (v[1] == "go1" && v[2] >= 13) { print "illumos"; } else { print "noillumos"; }}')
-bins-all:
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=freebsd   GOARCH=amd64
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=freebsd   GOARCH=386
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=linux     GOARCH=amd64
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=linux     GOARCH=arm64
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=linux     GOARCH=arm     GOARM=7
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=linux     GOARCH=386
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=darwin    GOARCH=amd64
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=solaris   GOARCH=amd64
-ifeq ($(GO_SUPPORTS_ILLUMOS), illumos)
-	$(MAKE) $(BINS_ALL_TARGETS) GOOS=illumos   GOARCH=amd64
-else ifeq ($(GO_SUPPORTS_ILLUMOS), noillumos)
-	@echo "SKIPPING ILLUMOS BUILD BECAUSE GO VERSION DOESN'T SUPPORT IT"
-else
-	@echo "CANNOT DETERMINE WHETHER GO VERSION SUPPORTS GOOS=illumos"; exit 1
-endif
+##################### MULTI-ARCH HELPERS #####################
+
+_run_make_foreach_target_tuple:
+	if [ "$(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG)" = "" ]; then \
+		echo "RUN_MAKE_FOREACH_TARGET_TUPLE_ARG must be set"; \
+		exit 1; \
+	fi
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=freebsd   GOARCH=amd64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=freebsd   GOARCH=386
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=freebsd   GOARCH=arm	  GOARM=7
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=freebsd   GOARCH=arm64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=linux     GOARCH=amd64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=linux     GOARCH=arm64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=linux     GOARCH=arm     GOARM=7
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=linux     GOARCH=386
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=darwin    GOARCH=amd64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=solaris   GOARCH=amd64
+	$(MAKE) $(RUN_MAKE_FOREACH_TARGET_TUPLE_ARG) GOOS=illumos   GOARCH=amd64
+
+##################### REGULAR TARGETS #####################
+.PHONY: lint test-go test-platform cover-merge cover-html vet zrepl-bin test-platform-bin generate-platform-test-list
 
 lint:
 	$(GO_ENV_VARS) $(GOLANGCI_LINT) run ./...
@@ -327,12 +353,12 @@ $(ARTIFACTDIR)/go_env.txt:
 
 docs: $(ARTIFACTDIR)/docs
 	# https://www.sphinx-doc.org/en/master/man/sphinx-build.html
-	make -C docs \
+	$(MAKE) -C docs \
 		html \
 		BUILDDIR=../artifacts/docs \
 		SPHINXOPTS="-W --keep-going -n"
 
 docs-clean:
-	make -C docs \
+	$(MAKE) -C docs \
 		clean \
 		BUILDDIR=../artifacts/docs

README.md

@@ -1,11 +1,12 @@
 [![GitHub license](https://img.shields.io/github/license/zrepl/zrepl.svg)](https://github.com/zrepl/zrepl/blob/master/LICENSE)
-[![Language: Go](https://img.shields.io/badge/language-Go-6ad7e5.svg)](https://golang.org/)
+[![Language: Go](https://img.shields.io/badge/lang-Go-6ad7e5.svg)](https://golang.org/)
 [![User Docs](https://img.shields.io/badge/docs-web-blue.svg)](https://zrepl.github.io)
-[![Support me on Patreon](https://img.shields.io/badge/dynamic/json?color=yellow&label=Patreon&query=data.attributes.patron_count&suffix=%20patrons&url=https%3A%2F%2Fwww.patreon.com%2Fapi%2Fcampaigns%2F3095079)](https://patreon.com/zrepl)
+[![Support me on Patreon](https://img.shields.io/badge/dynamic/json?color=yellow&label=Patreon&query=data.attributes.patron_count&url=https%3A%2F%2Fwww.patreon.com%2Fapi%2Fcampaigns%2F3095079)](https://patreon.com/zrepl)
 [![Donate via GitHub Sponsors](https://img.shields.io/static/v1?label=Sponsor&message=%E2%9D%A4&logo=GitHub&style=flat&color=yellow)](https://github.com/sponsors/problame)
 [![Donate via Liberapay](https://img.shields.io/liberapay/patrons/zrepl.svg?logo=liberapay)](https://liberapay.com/zrepl/donate)
 [![Donate via PayPal](https://img.shields.io/badge/donate-paypal-yellow.svg)](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=R5QSXJVYHGX96)
 [![Twitter](https://img.shields.io/twitter/url/https/github.com/zrepl/zrepl.svg?style=social)](https://twitter.com/intent/tweet?text=Wow:&url=https%3A%2F%2Fgithub.com%2Fzrepl%2Fzrepl)
+[![Chat](https://img.shields.io/badge/chat-matrix-blue.svg)](https://matrix.to/#/#zrepl:matrix.org)
 
 # zrepl
 zrepl is a one-stop ZFS backup & replication solution.
@@ -95,7 +96,7 @@ Downstream packagers can read the changelog to determine whether they want to pu
 
 ### Additional Notes to Distro Package Maintainers
 
-* Use `sudo make test-platform-bin && sudo make test-platform` **on a test system** to validate that zrepl's abstractions on top of ZFS work with the system ZFS.
+* Run the platform tests (Docs -> Usage -> Platform Tests) **on a test system** to validate that zrepl's abstractions on top of ZFS work with the system ZFS.
 * Ship a default config that adheres to your distro's `hier` and logging system.
 * Ship a service manager file and _please_ try to upstream it to this repository.
   * `dist/systemd` contains a Systemd unit template.

build.Dockerfile

@@ -2,12 +2,18 @@ FROM !SUBSTITUTED_BY_MAKEFILE
 
 RUN apt-get update && apt-get install -y \
     python3-pip \
+    python3-venv \
     unzip \
     gawk
 
 ADD build.installprotoc.bash ./
 RUN bash build.installprotoc.bash
 
+# setup venv
+ENV VIRTUAL_ENV=/opt/venv
+RUN python3 -m venv $VIRTUAL_ENV
+ENV PATH="$VIRTUAL_ENV/bin:$PATH"
+
 ADD lazy.sh /tmp/lazy.sh
 ADD docs/requirements.txt /tmp/requirements.txt
 ENV ZREPL_LAZY_DOCS_REQPATH=/tmp/requirements.txt

build/go.mod

@@ -4,13 +4,37 @@ go 1.12
 
 require (
 	github.com/alvaroloes/enumer v1.1.1
-	github.com/golangci/golangci-lint v1.35.2
-	github.com/golangci/misspell v0.3.4 // indirect
-	github.com/golangci/revgrep v0.0.0-20180812185044-276a5c0a1039 // indirect
-	github.com/spf13/afero v1.2.2 // indirect
-	github.com/spf13/jwalterweatherman v1.1.0 // indirect
+	github.com/breml/bidichk v0.2.6 // indirect
+	github.com/breml/errchkjson v0.3.5 // indirect
+	github.com/chavacava/garif v0.1.0 // indirect
+	github.com/daixiang0/gci v0.11.1 // indirect
+	github.com/golangci/golangci-lint v1.54.2
+	github.com/golangci/revgrep v0.5.0 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/jgautheron/goconst v1.6.0 // indirect
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/mattn/go-runewidth v0.0.15 // indirect
+	github.com/mgechev/revive v1.3.3 // indirect
+	github.com/pelletier/go-toml/v2 v2.1.0 // indirect
+	github.com/polyfloyd/go-errorlint v1.4.5 // indirect
+	github.com/prometheus/client_golang v1.16.0 // indirect
+	github.com/prometheus/common v0.44.0 // indirect
+	github.com/prometheus/procfs v0.11.1 // indirect
+	github.com/rivo/uniseg v0.4.4 // indirect
+	github.com/ryanrolds/sqlclosecheck v0.5.1 // indirect
+	github.com/spf13/viper v1.16.0 // indirect
+	github.com/stretchr/objx v0.5.1 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
+	github.com/tetafro/godot v1.4.15 // indirect
 	github.com/wadey/gocovmerge v0.0.0-20160331181800-b5bfa59ec0ad
-	golang.org/x/tools v0.0.0-20210105210202-9ed45478a130
-	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0 // indirect
-	google.golang.org/protobuf v1.25.0
+	github.com/xen0n/gosmopolitan v1.2.2 // indirect
+	gitlab.com/bosi/decorder v0.4.1 // indirect
+	go.uber.org/multierr v1.11.0 // indirect
+	go.uber.org/zap v1.25.0 // indirect
+	golang.org/x/exp v0.0.0-20230905200255-921286631fa9 // indirect
+	golang.org/x/exp/typeparams v0.0.0-20230905200255-921286631fa9 // indirect
+	golang.org/x/tools v0.13.0
+	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0
+	google.golang.org/protobuf v1.31.0
+	mvdan.cc/unparam v0.0.0-20230815095028-f7c6fb1088f0 // indirect
 )

build/tools.go

@@ -1,3 +1,4 @@
+//go:build tools
 // +build tools
 
 package main

client/configcheck.go

@@ -19,8 +19,9 @@ import (
 )
 
 var configcheckArgs struct {
-	format string
-	what   string
+	format        string
+	what          string
+	skipCertCheck bool
 }
 
 var ConfigcheckCmd = &cli.Subcommand{
@@ -29,6 +30,7 @@ var ConfigcheckCmd = &cli.Subcommand{
 	SetupFlags: func(f *pflag.FlagSet) {
 		f.StringVar(&configcheckArgs.format, "format", "", "dump parsed config object [pretty|yaml|json]")
 		f.StringVar(&configcheckArgs.what, "what", "all", "what to print [all|config|jobs|logging]")
+		f.BoolVar(&configcheckArgs.skipCertCheck, "skip-cert-check", false, "skip checking cert files")
 	},
 	Run: func(ctx context.Context, subcommand *cli.Subcommand, args []string) error {
 		formatMap := map[string]func(interface{}){
@@ -56,8 +58,16 @@ var ConfigcheckCmd = &cli.Subcommand{
 		}
 
 		var hadErr bool
+
+		parseFlags := config.ParseFlagsNone
+
+		if configcheckArgs.skipCertCheck {
+			parseFlags |= config.ParseFlagsNoCertCheck
+		}
+
 		// further: try to build jobs
-		confJobs, err := job.JobsFromConfig(subcommand.Config())
+		confJobs, err := job.JobsFromConfig(subcommand.Config(), parseFlags)
+
 		if err != nil {
 			err := errors.Wrap(err, "cannot build jobs from config")
 			if configcheckArgs.what == "jobs" {

client/migrate.go

@@ -129,7 +129,7 @@ func doMigrateReplicationCursor(ctx context.Context, sc *cli.Subcommand, args []
 	}
 
 	cfg := sc.Config()
-	jobs, err := job.JobsFromConfig(cfg)
+	jobs, err := job.JobsFromConfig(cfg, config.ParseFlagsNone)
 	if err != nil {
 		fmt.Printf("cannot parse config:\n%s\n\n", err)
 		fmt.Printf("NOTE: this migration was released together with a change in job name requirements.\n")

client/status/client/client.go

@@ -14,11 +14,11 @@ import (
 )
 
 type Client struct {
-	h http.Client
+	h *http.Client
 }
 
 func New(network, addr string) (*Client, error) {
-	httpc, err := controlHttpClient(func(_ context.Context) (net.Conn, error) { return net.Dial(network, addr) })
+	httpc, err := makeControlHttpClient(func(_ context.Context) (net.Conn, error) { return net.Dial(network, addr) })
 	if err != nil {
 		return nil, err
 	}
@@ -63,8 +63,8 @@ func (c *Client) SignalReset(job string) error {
 	return c.signal(job, "reset")
 }
 
-func controlHttpClient(dialfunc func(context.Context) (net.Conn, error)) (client http.Client, err error) {
-	return http.Client{
+func makeControlHttpClient(dialfunc func(context.Context) (net.Conn, error)) (client *http.Client, err error) {
+	return &http.Client{
 		Transport: &http.Transport{
 			DialContext: func(ctx context.Context, _, _ string) (net.Conn, error) {
 				return dialfunc(ctx)
@@ -73,14 +73,24 @@ func controlHttpClient(dialfunc func(context.Context) (net.Conn, error)) (client
 	}, nil
 }
 
-func jsonRequestResponse(c http.Client, endpoint string, req interface{}, res interface{}) error {
+func jsonRequestResponse(c *http.Client, endpoint string, req interface{}, res interface{}) error {
 	var buf bytes.Buffer
 	encodeErr := json.NewEncoder(&buf).Encode(req)
 	if encodeErr != nil {
 		return encodeErr
 	}
 
-	resp, err := c.Post("http://unix"+endpoint, "application/json", &buf)
+	hreq, err := http.NewRequest("POST", "http://unix"+endpoint, &buf)
+	if err != nil {
+		return err
+	}
+	hreq.Header.Set("Content-Type", "application/json")
+	// Prevent EOF errors when client request frequency and server keepalive close are at the same time.
+	// Found this by watching http.Server.ConnState changes, then found
+	// https://stackoverflow.com/questions/17714494/golang-http-request-results-in-eof-errors-when-making-multiple-requests-successi
+	// Note: The issue seems even more prounounced with local TCP sockets than unix domain sockets. So, I used that for debugging.
+	hreq.Close = true
+	resp, err := c.Do(hreq)
 	if err != nil {
 		return err
 	}

client/status/status_interactive.go

@@ -129,7 +129,7 @@ func interactive(c Client, flag statusFlags) error {
 		FSFilter:                func(_ string) bool { return true },
 		DetailViewWidth:         100,
 		DetailViewWrap:          false,
-		ShortKeybindingOverview: "[::b]Q[::-] quit  [::b]<TAB>[::-] switch panes  [::b]Shift+M[::-] toggle navbar  [::b]Shift+S[::-] signal job [::b]</>[::-] filter filesystems",
+		ShortKeybindingOverview: "[::b]Q[::-] quit  [::b]<TAB>[::-] switch panes [::b]W[::-] wrap lines  [::b]Shift+M[::-] toggle navbar  [::b]Shift+S[::-] signal job [::b]</>[::-] filter filesystems",
 	}
 	paramsMtx := &sync.Mutex{}
 	var redraw func()

client/status/viewmodel/bytecountbinary.go

@@ -2,14 +2,22 @@ package viewmodel
 
 import (
 	"fmt"
+	"math"
 )
 
+func ByteCountBinaryUint(b uint64) string {
+	if b > math.MaxInt64 {
+		panic(b)
+	}
+	return ByteCountBinary(int64(b))
+}
+
 func ByteCountBinary(b int64) string {
 	const unit = 1024
 	if b < unit {
 		return fmt.Sprintf("%d B", b)
 	}
-	div, exp := int64(unit), 0
+	div, exp := unit, 0
 	for n := b / unit; n >= unit; n /= unit {
 		div *= unit
 		exp++

client/status/viewmodel/bytesprogresshistory.go

@@ -4,17 +4,16 @@ import "time"
 
 type byteProgressMeasurement struct {
 	time time.Time
-	val  int64
+	val  uint64
 }
 
 type bytesProgressHistory struct {
 	last        *byteProgressMeasurement // pointer as poor man's optional
 	changeCount int
 	lastChange  time.Time
-	bpsAvg      float64
 }
 
-func (p *bytesProgressHistory) Update(currentVal int64) (bytesPerSecondAvg int64, changeCount int) {
+func (p *bytesProgressHistory) Update(currentVal uint64) (bytesPerSecondAvg int64, changeCount int) {
 
 	if p.last == nil {
 		p.last = &byteProgressMeasurement{
@@ -34,15 +33,17 @@ func (p *bytesProgressHistory) Update(currentVal int64) (bytesPerSecondAvg int64
 		return 0, 0
 	}
 
-	deltaV := currentVal - p.last.val
+	var deltaV int64
+	if currentVal >= p.last.val {
+		deltaV = int64(currentVal - p.last.val)
+	} else {
+		deltaV = -int64(p.last.val - currentVal)
+	}
 	deltaT := time.Since(p.last.time)
 	rate := float64(deltaV) / deltaT.Seconds()
 
-	factor := 0.3
-	p.bpsAvg = (1-factor)*p.bpsAvg + factor*rate
-
 	p.last.time = time.Now()
 	p.last.val = currentVal
 
-	return int64(p.bpsAvg), p.changeCount
+	return int64(rate), p.changeCount
 }

client/status/viewmodel/render.go

@@ -216,7 +216,7 @@ func drawJob(t *stringbuilder.B, name string, v *job.Status, history *bytesProgr
 	}
 }
 
-func printFilesystemStatus(t *stringbuilder.B, rep *report.FilesystemReport, active bool, maxFS int) {
+func printFilesystemStatus(t *stringbuilder.B, rep *report.FilesystemReport, maxFS int) {
 
 	expected, replicated, containsInvalidSizeEstimates := rep.BytesSum()
 	sizeEstimationImpreciseNotice := ""
@@ -227,15 +227,28 @@ func printFilesystemStatus(t *stringbuilder.B, rep *report.FilesystemReport, act
 		sizeEstimationImpreciseNotice = " (step lacks size estimation)"
 	}
 
+	userVisisbleCurrentStep, userVisibleTotalSteps := rep.CurrentStep, len(rep.Steps)
+	// `.CurrentStep` is == len(rep.Steps) if all steps are done.
+	// Until then, it's an index into .Steps that starts at 0.
+	// For the user, we want it to start at 1.
+	if rep.CurrentStep >= len(rep.Steps) {
+		// rep.CurrentStep is what we want to show.
+		// We check for >= and not == for robustness.
+	} else {
+		// We're not done yet, so, make step count start at 1
+		// (The `.State` is included in the output, indicating we're not done yet)
+		userVisisbleCurrentStep = rep.CurrentStep + 1
+	}
 	status := fmt.Sprintf("%s (step %d/%d, %s/%s)%s",
 		strings.ToUpper(string(rep.State)),
-		rep.CurrentStep, len(rep.Steps),
-		ByteCountBinary(replicated), ByteCountBinary(expected),
+		userVisisbleCurrentStep, userVisibleTotalSteps,
+		ByteCountBinaryUint(replicated), ByteCountBinaryUint(expected),
 		sizeEstimationImpreciseNotice,
 	)
 
 	activeIndicator := " "
-	if active {
+	if rep.BlockedOn == report.FsBlockedOnNothing &&
+		(rep.State == report.FilesystemPlanning || rep.State == report.FilesystemStepping) {
 		activeIndicator = "*"
 	}
 	t.AddIndent(1)
@@ -260,9 +273,9 @@ func printFilesystemStatus(t *stringbuilder.B, rep *report.FilesystemReport, act
 				attribs = append(attribs, "resumed")
 			}
 
-			attribs = append(attribs, fmt.Sprintf("encrypted=%s", nextStep.Info.Encrypted))
-
-			next += fmt.Sprintf(" (%s)", strings.Join(attribs, ", "))
+			if len(attribs) > 0 {
+				next += fmt.Sprintf(" (%s)", strings.Join(attribs, ", "))
+			}
 		} else {
 			next = "" // individual FSes may still be in planning state
 		}
@@ -356,10 +369,20 @@ func renderReplicationReport(t *stringbuilder.B, rep *report.Report, history *by
 		// Progress: [---------------]
 		expected, replicated, containsInvalidSizeEstimates := latest.BytesSum()
 		rate, changeCount := history.Update(replicated)
-		t.Write("Progress: ")
-		t.DrawBar(50, replicated, expected, changeCount)
-		t.Write(fmt.Sprintf(" %s / %s @ %s/s", ByteCountBinary(replicated), ByteCountBinary(expected), ByteCountBinary(rate)))
-		t.Newline()
+		eta := time.Duration(0)
+		if rate > 0 {
+			eta = time.Duration((float64(expected)-float64(replicated))/float64(rate)) * time.Second
+		}
+
+		if !latest.State.IsTerminal() {
+			t.Write("Progress: ")
+			t.DrawBar(50, replicated, expected, changeCount)
+			t.Write(fmt.Sprintf(" %s / %s @ %s/s", ByteCountBinaryUint(replicated), ByteCountBinaryUint(expected), ByteCountBinary(rate)))
+			if eta != 0 {
+				t.Write(fmt.Sprintf(" (%s remaining)", humanizeDuration(eta)))
+			}
+			t.Newline()
+		}
 		if containsInvalidSizeEstimates {
 			t.Write("NOTE: not all steps could be size-estimated, total estimate is likely imprecise!")
 			t.Newline()
@@ -377,12 +400,36 @@ func renderReplicationReport(t *stringbuilder.B, rep *report.Report, history *by
 			}
 		}
 		for _, fs := range latest.Filesystems {
-			printFilesystemStatus(t, fs, false, maxFSLen) // FIXME bring 'active' flag back
+			printFilesystemStatus(t, fs, maxFSLen)
 		}
 
 	}
 }
 
+func humanizeDuration(duration time.Duration) string {
+	days := int64(duration.Hours() / 24)
+	hours := int64(math.Mod(duration.Hours(), 24))
+	minutes := int64(math.Mod(duration.Minutes(), 60))
+	seconds := int64(math.Mod(duration.Seconds(), 60))
+
+	var parts []string
+
+	force := false
+	chunks := []int64{days, hours, minutes, seconds}
+	for i, chunk := range chunks {
+		if force || chunk > 0 {
+			padding := 0
+			if force {
+				padding = 2
+			}
+			parts = append(parts, fmt.Sprintf("%*d%c", padding, chunk, "dhms"[i]))
+			force = true
+		}
+	}
+
+	return strings.Join(parts, " ")
+}
+
 func renderPrunerReport(t *stringbuilder.B, r *pruner.Report, fsfilter FilterFunc) {
 	if r == nil {
 		t.Printf("...\n")
@@ -448,15 +495,17 @@ func renderPrunerReport(t *stringbuilder.B, r *pruner.Report, fsfilter FilterFun
 	}
 
 	// global progress bar
-	progress := int(math.Round(80 * float64(completedDestroyCount) / float64(totalDestroyCount)))
-	t.Write("Progress: ")
-	t.Write("[")
-	t.Write(stringbuilder.Times("=", progress))
-	t.Write(">")
-	t.Write(stringbuilder.Times("-", 80-progress))
-	t.Write("]")
-	t.Printf(" %d/%d snapshots", completedDestroyCount, totalDestroyCount)
-	t.Newline()
+	if !state.IsTerminal() {
+		progress := int(math.Round(80 * float64(completedDestroyCount) / float64(totalDestroyCount)))
+		t.Write("Progress: ")
+		t.Write("[")
+		t.Write(stringbuilder.Times("=", progress))
+		t.Write(">")
+		t.Write(stringbuilder.Times("-", 80-progress))
+		t.Write("]")
+		t.Printf(" %d/%d snapshots", completedDestroyCount, totalDestroyCount)
+		t.Newline()
+	}
 
 	sort.SliceStable(all, func(i, j int) bool {
 		return strings.Compare(all[i].Filesystem, all[j].Filesystem) == -1
@@ -502,10 +551,20 @@ func renderPrunerReport(t *stringbuilder.B, r *pruner.Report, fsfilter FilterFun
 
 func renderSnapperReport(t *stringbuilder.B, r *snapper.Report, fsfilter FilterFunc) {
 	if r == nil {
-		t.Printf("<snapshot type does not have a report>\n")
+		t.Printf("<no snapshotting report available>\n")
 		return
 	}
+	t.Printf("Type: %s\n", r.Type)
+	if r.Periodic != nil {
+		renderSnapperReportPeriodic(t, r.Periodic, fsfilter)
+	} else if r.Cron != nil {
+		renderSnapperReportCron(t, r.Cron, fsfilter)
+	} else {
+		t.Printf("<no details available>")
+	}
+}
 
+func renderSnapperReportPeriodic(t *stringbuilder.B, r *snapper.PeriodicReport, fsfilter FilterFunc) {
 	t.Printf("Status: %s", r.State)
 	t.Newline()
 
@@ -516,8 +575,25 @@ func renderSnapperReport(t *stringbuilder.B, r *snapper.Report, fsfilter FilterF
 		t.Printf("Sleep until: %s\n", r.SleepUntil)
 	}
 
-	sort.Slice(r.Progress, func(i, j int) bool {
-		return strings.Compare(r.Progress[i].Path, r.Progress[j].Path) == -1
+	renderSnapperPlanReportFilesystem(t, r.Progress, fsfilter)
+}
+
+func renderSnapperReportCron(t *stringbuilder.B, r *snapper.CronReport, fsfilter FilterFunc) {
+	t.Printf("State: %s\n", r.State)
+
+	now := time.Now()
+	if r.WakeupTime.After(now) {
+		t.Printf("Sleep until: %s (%s remaining)\n", r.WakeupTime, r.WakeupTime.Sub(now).Round(time.Second))
+	} else {
+		t.Printf("Started: %s (lasting %s)\n", r.WakeupTime, now.Sub(r.WakeupTime).Round(time.Second))
+	}
+
+	renderSnapperPlanReportFilesystem(t, r.Progress, fsfilter)
+}
+
+func renderSnapperPlanReportFilesystem(t *stringbuilder.B, fss []*snapper.ReportFilesystem, fsfilter FilterFunc) {
+	sort.Slice(fss, func(i, j int) bool {
+		return strings.Compare(fss[i].Path, fss[j].Path) == -1
 	})
 
 	dur := func(d time.Duration) string {
@@ -530,8 +606,8 @@ func renderSnapperReport(t *stringbuilder.B, r *snapper.Report, fsfilter FilterF
 	var widths struct {
 		path, state, duration int
 	}
-	rows := make([]*row, 0, len(r.Progress))
-	for _, fs := range r.Progress {
+	rows := make([]*row, 0, len(fss))
+	for _, fs := range fss {
 		if !fsfilter(fs.Path) {
 			continue
 		}
@@ -574,9 +650,11 @@ func renderSnapperReport(t *stringbuilder.B, r *snapper.Report, fsfilter FilterF
 		t.Printf("%s %s %s", path, state, duration)
 		t.PrintfDrawIndentedAndWrappedIfMultiline(" %s", r.remainder)
 		if r.hookReport != "" {
-			t.PrintfDrawIndentedAndWrappedIfMultiline("%s", r.hookReport)
+			t.AddIndent(1)
+			t.Newline()
+			t.Printf("%s", r.hookReport)
+			t.AddIndent(-1)
 		}
 		t.Newline()
 	}
-
 }

client/status/viewmodel/stringbuilder/stringbuilder.go

@@ -99,11 +99,11 @@ func RightPad(str string, length int, pad string) string {
 }
 
 // changeCount = 0 indicates stall / no progress
-func (w *B) DrawBar(length int, bytes, totalBytes int64, changeCount int) {
+func (w *B) DrawBar(length int, bytes, totalBytes uint64, changeCount int) {
 	const arrowPositions = `>\|/`
 	var completedLength int
 	if totalBytes > 0 {
-		completedLength = int(int64(length) * bytes / totalBytes)
+		completedLength = int(uint64(length) * bytes / totalBytes)
 		if completedLength > length {
 			completedLength = length
 		}

client/testcmd.go

@@ -139,9 +139,11 @@ var testPlaceholder = &cli.Subcommand{
 func runTestPlaceholder(ctx context.Context, subcommand *cli.Subcommand, args []string) error {
 
 	var checkDPs []*zfs.DatasetPath
+	var datasetWasExplicitArgument bool
 
 	// all actions first
 	if testPlaceholderArgs.all {
+		datasetWasExplicitArgument = false
 		out, err := zfs.ZFSList(ctx, []string{"name"})
 		if err != nil {
 			return errors.Wrap(err, "could not list ZFS filesystems")
@@ -154,6 +156,7 @@ func runTestPlaceholder(ctx context.Context, subcommand *cli.Subcommand, args []
 			checkDPs = append(checkDPs, dp)
 		}
 	} else {
+		datasetWasExplicitArgument = true
 		dp, err := zfs.NewDatasetPath(testPlaceholderArgs.ds)
 		if err != nil {
 			return err
@@ -171,7 +174,12 @@ func runTestPlaceholder(ctx context.Context, subcommand *cli.Subcommand, args []
 			return errors.Wrap(err, "cannot get placeholder state")
 		}
 		if !ph.FSExists {
-			panic("placeholder state inconsistent: filesystem " + ph.FS + " must exist in this context")
+			if datasetWasExplicitArgument {
+				return errors.Errorf("filesystem %q does not exist", ph.FS)
+			} else {
+				// got deleted between ZFSList and ZFSGetFilesystemPlaceholderState
+				continue
+			}
 		}
 		is := "yes"
 		if !ph.IsPlaceholder {

client/zfsabstractions.go

@@ -57,7 +57,7 @@ func (f *zabsFilterFlags) registerZabsFilterFlags(s *pflag.FlagSet, verb string)
 	for v := range endpoint.AbstractionTypesAll {
 		variants = append(variants, string(v))
 	}
-	variants = sort.StringSlice(variants)
+	sort.Strings(variants)
 	variantsJoined := strings.Join(variants, "|")
 	s.Var(&f.Types, "type", fmt.Sprintf("only %s holds of the specified type [default: all] [comma-separated list of %s]", verb, variantsJoined))
 

client/zfsabstractions_list.go

@@ -44,10 +44,11 @@ func doZabsList(ctx context.Context, sc *cli.Subcommand, args []string) error {
 		return errors.Wrap(err, "invalid filter specification on command line")
 	}
 
-	abstractions, errors, err := endpoint.ListAbstractionsStreamed(ctx, q)
+	abstractions, errors, drainDone, err := endpoint.ListAbstractionsStreamed(ctx, q)
 	if err != nil {
 		return err // context clear by invocation of command
 	}
+	defer drainDone()
 
 	var line chainlock.L
 	var wg sync.WaitGroup

config/config.go

@@ -6,16 +6,23 @@ import (
 	"log/syslog"
 	"os"
 	"reflect"
-	"regexp"
-	"strconv"
 	"time"
 
 	"github.com/pkg/errors"
+	"github.com/robfig/cron/v3"
 	"github.com/zrepl/yaml-config"
 
+	"github.com/zrepl/zrepl/util/datasizeunit"
 	zfsprop "github.com/zrepl/zrepl/zfs/property"
 )
 
+type ParseFlags uint
+
+const (
+	ParseFlagsNone        ParseFlags = 0
+	ParseFlagsNoCertCheck ParseFlags = 1 << iota
+)
+
 type Config struct {
 	Jobs   []JobEnum `yaml:"jobs"`
 	Global *Global   `yaml:"global,optional,fromdefaults"`
@@ -54,26 +61,28 @@ func (j JobEnum) Name() string {
 }
 
 type ActiveJob struct {
-	Type        string                `yaml:"type"`
-	Name        string                `yaml:"name"`
-	Connect     ConnectEnum           `yaml:"connect"`
-	Pruning     PruningSenderReceiver `yaml:"pruning"`
-	Debug       JobDebugSettings      `yaml:"debug,optional"`
-	Replication *Replication          `yaml:"replication,optional,fromdefaults"`
+	Type               string                `yaml:"type"`
+	Name               string                `yaml:"name"`
+	Connect            ConnectEnum           `yaml:"connect"`
+	Pruning            PruningSenderReceiver `yaml:"pruning"`
+	Replication        *Replication          `yaml:"replication,optional,fromdefaults"`
+	ConflictResolution *ConflictResolution   `yaml:"conflict_resolution,optional,fromdefaults"`
+}
+
+type ConflictResolution struct {
+	InitialReplication string `yaml:"initial_replication,optional,default=most_recent"`
 }
 
 type PassiveJob struct {
-	Type  string           `yaml:"type"`
-	Name  string           `yaml:"name"`
-	Serve ServeEnum        `yaml:"serve"`
-	Debug JobDebugSettings `yaml:"debug,optional"`
+	Type  string    `yaml:"type"`
+	Name  string    `yaml:"name"`
+	Serve ServeEnum `yaml:"serve"`
 }
 
 type SnapJob struct {
 	Type         string            `yaml:"type"`
 	Name         string            `yaml:"name"`
 	Pruning      PruningLocal      `yaml:"pruning"`
-	Debug        JobDebugSettings  `yaml:"debug,optional"`
 	Snapshotting SnapshottingEnum  `yaml:"snapshotting"`
 	Filesystems  FilesystemsFilter `yaml:"filesystems"`
 }
@@ -85,8 +94,10 @@ type SendOptions struct {
 	BackupProperties bool `yaml:"backup_properties,optional,default=false"`
 	LargeBlocks      bool `yaml:"large_blocks,optional,default=false"`
 	Compressed       bool `yaml:"compressed,optional,default=false"`
-	EmbeddedData     bool `yaml:"embbeded_data,optional,default=false"`
+	EmbeddedData     bool `yaml:"embedded_data,optional,default=false"`
 	Saved            bool `yaml:"saved,optional,default=false"`
+
+	BandwidthLimit *BandwidthLimit `yaml:"bandwidth_limit,optional,fromdefaults"`
 }
 
 type RecvOptions struct {
@@ -96,9 +107,21 @@ type RecvOptions struct {
 	// Reencrypt bool `yaml:"reencrypt"`
 
 	Properties *PropertyRecvOptions `yaml:"properties,fromdefaults"`
+
+	BandwidthLimit *BandwidthLimit `yaml:"bandwidth_limit,optional,fromdefaults"`
+
+	Placeholder *PlaceholderRecvOptions `yaml:"placeholder,fromdefaults"`
+}
+
+var _ yaml.Unmarshaler = &datasizeunit.Bits{}
+
+type BandwidthLimit struct {
+	Max            datasizeunit.Bits `yaml:"max,default=-1 B"`
+	BucketCapacity datasizeunit.Bits `yaml:"bucket_capacity,default=128 KiB"`
 }
 
 type Replication struct {
+	Triggers    []*ReplicationTriggerEnum
 	Protection  *ReplicationOptionsProtection  `yaml:"protection,optional,fromdefaults"`
 	Concurrency *ReplicationOptionsConcurrency `yaml:"concurrency,optional,fromdefaults"`
 }
@@ -113,8 +136,30 @@ type ReplicationOptionsConcurrency struct {
 	SizeEstimates int `yaml:"size_estimates,optional,default=4"`
 }
 
-func (l *RecvOptions) SetDefault() {
-	*l = RecvOptions{Properties: &PropertyRecvOptions{}}
+type ReplicationTriggerEnum struct {
+	Ret interface{}
+}
+
+func (t *ReplicationTriggerEnum) UnmarshalYAML(u func(interface{}, bool) error) (err error) {
+	t.Ret, err = enumUnmarshal(u, map[string]interface{}{
+		"manual":   &ReplicationTriggerManual{},
+		"periodic": &ReplicationTriggerPeriodic{},
+	})
+	return
+}
+
+type ReplicationTriggerManual struct {
+	Type string `yaml:"type"`
+}
+
+type ReplicationTriggerPeriodic struct {
+	Type     string            `yaml:"type"`
+	Interval *PositiveDuration `yaml:"interval"`
+}
+
+type ReplicationTriggerCron struct {
+	Type string   `yaml:"type"`
+	Cron CronSpec `yaml:"cron"`
 }
 
 type PropertyRecvOptions struct {
@@ -122,6 +167,10 @@ type PropertyRecvOptions struct {
 	Override map[zfsprop.Property]string `yaml:"override,optional"`
 }
 
+type PlaceholderRecvOptions struct {
+	Encryption string `yaml:"encryption,default=unspecified"`
+}
+
 type PushJob struct {
 	ActiveJob    `yaml:",inline"`
 	Snapshotting SnapshottingEnum  `yaml:"snapshotting"`
@@ -135,7 +184,6 @@ func (j *PushJob) GetSendOptions() *SendOptions      { return j.Send }
 type PullJob struct {
 	ActiveJob `yaml:",inline"`
 	RootFS    string                   `yaml:"root_fs"`
-	Interval  PositiveDurationOrManual `yaml:"interval"`
 	Recv      *RecvOptions             `yaml:"recv,fromdefaults,optional"`
 }
 
@@ -163,13 +211,10 @@ func (i *PositiveDurationOrManual) UnmarshalYAML(u func(interface{}, bool) error
 		return fmt.Errorf("value must not be empty")
 	default:
 		i.Manual = false
-		i.Interval, err = time.ParseDuration(s)
+		i.Interval, err = parsePositiveDuration(s)
 		if err != nil {
 			return err
 		}
-		if i.Interval <= 0 {
-			return fmt.Errorf("value must be a positive duration, got %q", s)
-		}
 	}
 	return nil
 }
@@ -201,10 +246,44 @@ type SnapshottingEnum struct {
 }
 
 type SnapshottingPeriodic struct {
-	Type     string        `yaml:"type"`
-	Prefix   string        `yaml:"prefix"`
-	Interval time.Duration `yaml:"interval,positive"`
-	Hooks    HookList      `yaml:"hooks,optional"`
+	Type            string            `yaml:"type"`
+	Prefix          string            `yaml:"prefix"`
+	Interval        *PositiveDuration `yaml:"interval"`
+	Hooks           HookList          `yaml:"hooks,optional"`
+	TimestampFormat string            `yaml:"timestamp_format,optional,default=dense"`
+}
+
+type CronSpec struct {
+	Schedule cron.Schedule
+}
+
+var _ yaml.Unmarshaler = &CronSpec{}
+
+func (s *CronSpec) UnmarshalYAML(unmarshal func(v interface{}, not_strict bool) error) error {
+	var specString string
+	if err := unmarshal(&specString, false); err != nil {
+		return err
+	}
+
+	// Use standard cron format.
+	// Disable the various "descriptors" (@daily, etc)
+	// They are just aliases to "top of hour", "midnight", etc.
+	parser := cron.NewParser(cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow | cron.SecondOptional)
+
+	sched, err := parser.Parse(specString)
+	if err != nil {
+		return errors.Wrap(err, "cron syntax invalid")
+	}
+	s.Schedule = sched
+	return nil
+}
+
+type SnapshottingCron struct {
+	Type            string   `yaml:"type"`
+	Prefix          string   `yaml:"prefix"`
+	Cron            CronSpec `yaml:"cron"`
+	Hooks           HookList `yaml:"hooks,optional"`
+	TimestampFormat string   `yaml:"timestamp_format,optional,default=dense"`
 }
 
 type SnapshottingManual struct {
@@ -424,14 +503,6 @@ type GlobalStdinServer struct {
 	SockDir string `yaml:"sockdir,default=/var/run/zrepl/stdinserver"`
 }
 
-type JobDebugSettings struct {
-	Conn *struct {
-		ReadDump  string `yaml:"read_dump"`
-		WriteDump string `yaml:"write_dump"`
-	} `yaml:"conn,optional"`
-	RPCLog bool `yaml:"rpc_log,optional,default=false"`
-}
-
 type HookList []HookEnum
 
 type HookEnum struct {
@@ -530,6 +601,7 @@ func (t *SnapshottingEnum) UnmarshalYAML(u func(interface{}, bool) error) (err e
 	t.Ret, err = enumUnmarshal(u, map[string]interface{}{
 		"periodic": &SnapshottingPeriodic{},
 		"manual":   &SnapshottingManual{},
+		"cron":     &SnapshottingCron{},
 	})
 	return
 }
@@ -655,41 +727,3 @@ func ParseConfigBytes(bytes []byte) (*Config, error) {
 	}
 	return c, nil
 }
-
-var durationStringRegex *regexp.Regexp = regexp.MustCompile(`^\s*(\d+)\s*(s|m|h|d|w)\s*$`)
-
-func parsePositiveDuration(e string) (d time.Duration, err error) {
-	comps := durationStringRegex.FindStringSubmatch(e)
-	if len(comps) != 3 {
-		err = fmt.Errorf("does not match regex: %s %#v", e, comps)
-		return
-	}
-
-	durationFactor, err := strconv.ParseInt(comps[1], 10, 64)
-	if err != nil {
-		return 0, err
-	}
-	if durationFactor <= 0 {
-		return 0, errors.New("duration must be positive integer")
-	}
-
-	var durationUnit time.Duration
-	switch comps[2] {
-	case "s":
-		durationUnit = time.Second
-	case "m":
-		durationUnit = time.Minute
-	case "h":
-		durationUnit = time.Hour
-	case "d":
-		durationUnit = 24 * time.Hour
-	case "w":
-		durationUnit = 24 * 7 * time.Hour
-	default:
-		err = fmt.Errorf("contains unknown time unit '%s'", comps[2])
-		return
-	}
-
-	d = time.Duration(durationFactor) * durationUnit
-	return
-}

config/config_duration.go

@@ -0,0 +1,106 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"time"
+
+	"github.com/kr/pretty"
+	"github.com/zrepl/yaml-config"
+)
+
+type Duration struct{ d time.Duration }
+
+func (d Duration) Duration() time.Duration { return d.d }
+
+var _ yaml.Unmarshaler = &Duration{}
+
+func (d *Duration) UnmarshalYAML(unmarshal func(v interface{}, not_strict bool) error) error {
+	var s string
+	err := unmarshal(&s, false)
+	if err != nil {
+		return err
+	}
+	d.d, err = parseDuration(s)
+	if err != nil {
+		d.d = 0
+		return &yaml.TypeError{Errors: []string{fmt.Sprintf("cannot parse value %q: %s", s, err)}}
+	}
+	return nil
+}
+
+type PositiveDuration struct{ d Duration }
+
+var _ yaml.Unmarshaler = &PositiveDuration{}
+
+func (d PositiveDuration) Duration() time.Duration { return d.d.Duration() }
+
+func (d *PositiveDuration) UnmarshalYAML(unmarshal func(v interface{}, not_strict bool) error) error {
+	err := d.d.UnmarshalYAML(unmarshal)
+	if err != nil {
+		return err
+	}
+	if d.d.Duration() <= 0 {
+		return fmt.Errorf("duration must be positive, got %s", d.d.Duration())
+	}
+	return nil
+}
+
+func parsePositiveDuration(e string) (time.Duration, error) {
+	d, err := parseDuration(e)
+	if err != nil {
+		return d, err
+	}
+	if d <= 0 {
+		return 0, errors.New("duration must be positive integer")
+	}
+	return d, err
+}
+
+var durationStringRegex *regexp.Regexp = regexp.MustCompile(`^\s*([\+-]?\d+)\s*(|s|m|h|d|w)\s*$`)
+
+func parseDuration(e string) (d time.Duration, err error) {
+	comps := durationStringRegex.FindStringSubmatch(e)
+	if comps == nil {
+		err = fmt.Errorf("must match %s", durationStringRegex)
+		return
+	}
+	if len(comps) != 3 {
+		panic(pretty.Sprint(comps))
+	}
+
+	durationFactor, err := strconv.ParseInt(comps[1], 10, 64)
+	if err != nil {
+		return 0, err
+	}
+
+	var durationUnit time.Duration
+	switch comps[2] {
+	case "":
+		if durationFactor != 0 {
+			err = fmt.Errorf("missing time unit")
+			return
+		} else {
+			// It's the case where user specified '0'.
+			// We want to allow this, just like time.ParseDuration.
+		}
+	case "s":
+		durationUnit = time.Second
+	case "m":
+		durationUnit = time.Minute
+	case "h":
+		durationUnit = time.Hour
+	case "d":
+		durationUnit = 24 * time.Hour
+	case "w":
+		durationUnit = 24 * 7 * time.Hour
+	default:
+		err = fmt.Errorf("contains unknown time unit '%s'", comps[2])
+		return
+	}
+
+	d = time.Duration(durationFactor) * durationUnit
+	return
+}

config/config_snapshotting_test.go

@@ -35,8 +35,23 @@ jobs:
   snapshotting:
     type: periodic
     prefix: zrepl_
+    timestamp_format: dense
     interval: 10m
 `
+	cron := `
+  snapshotting:
+    type: cron
+    prefix: zrepl_
+    timestamp_format: human
+    cron: "10 * * * *"
+`
+
+	periodicDaily := `
+  snapshotting:
+    type: periodic
+    prefix: zrepl_
+    interval: 1d
+`
 
 	hooks := `
   snapshotting:
@@ -74,10 +89,27 @@ jobs:
 		c = testValidConfig(t, fillSnapshotting(periodic))
 		snp := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingPeriodic)
 		assert.Equal(t, "periodic", snp.Type)
-		assert.Equal(t, 10*time.Minute, snp.Interval)
+		assert.Equal(t, 10*time.Minute, snp.Interval.Duration())
 		assert.Equal(t, "zrepl_", snp.Prefix)
 	})
 
+	t.Run("periodicDaily", func(t *testing.T) {
+		c = testValidConfig(t, fillSnapshotting(periodicDaily))
+		snp := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingPeriodic)
+		assert.Equal(t, "periodic", snp.Type)
+		assert.Equal(t, 24*time.Hour, snp.Interval.Duration())
+		assert.Equal(t, "zrepl_", snp.Prefix)
+		assert.Equal(t, "dense", snp.TimestampFormat)
+	})
+
+	t.Run("cron", func(t *testing.T) {
+		c = testValidConfig(t, fillSnapshotting(cron))
+		snp := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingCron)
+		assert.Equal(t, "cron", snp.Type)
+		assert.Equal(t, "zrepl_", snp.Prefix)
+		assert.Equal(t, "human", snp.TimestampFormat)
+	})
+
 	t.Run("hooks", func(t *testing.T) {
 		c = testValidConfig(t, fillSnapshotting(hooks))
 		hs := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingPeriodic).Hooks
@@ -88,3 +120,57 @@ jobs:
 	})
 
 }
+
+func TestSnapshottingTimestampDefaults(t *testing.T) {
+	tmpl := `
+jobs:
+- name: foo
+  type: push
+  connect:
+    type: local
+    listener_name: foo
+    client_identity: bar
+  filesystems: {"<": true}
+  %s
+  pruning:
+    keep_sender:
+    - type: last_n
+      count: 10
+    keep_receiver:
+    - type: last_n
+      count: 10
+`
+
+	periodic := `
+  snapshotting:
+    type: periodic
+    prefix: zrepl_
+    interval: 10m
+`
+	cron := `
+  snapshotting:
+    type: cron
+    prefix: zrepl_
+    cron: "10 * * * *"
+`
+
+	fillSnapshotting := func(s string) string { return fmt.Sprintf(tmpl, s) }
+	var c *Config
+
+	t.Run("periodic", func(t *testing.T) {
+		c = testValidConfig(t, fillSnapshotting(periodic))
+		snp := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingPeriodic)
+		assert.Equal(t, "periodic", snp.Type)
+		assert.Equal(t, 10*time.Minute, snp.Interval.Duration())
+		assert.Equal(t, "zrepl_", snp.Prefix)
+		assert.Equal(t, "dense", snp.TimestampFormat) // default was set correctly
+	})
+
+	t.Run("cron", func(t *testing.T) {
+		c = testValidConfig(t, fillSnapshotting(cron))
+		snp := c.Jobs[0].Ret.(*PushJob).Snapshotting.Ret.(*SnapshottingCron)
+		assert.Equal(t, "cron", snp.Type)
+		assert.Equal(t, "zrepl_", snp.Prefix)
+		assert.Equal(t, "dense", snp.TimestampFormat) // default was set correctly
+	})
+}

config/config_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/kr/pretty"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"github.com/zrepl/yaml-config"
 )
 
 func TestSampleConfigsAreParsedWithoutErrors(t *testing.T) {
@@ -43,7 +44,8 @@ func TestSampleConfigsAreParsedWithoutErrors(t *testing.T) {
 }
 
 // template must be a template/text template with a single '{{ . }}' as placeholder for val
-//nolint[:deadcode,unused]
+//
+//nolint:deadcode,unused
 func testValidConfigTemplate(t *testing.T, tmpl string, val string) *Config {
 	tmp, err := template.New("master").Parse(tmpl)
 	if err != nil {
@@ -86,3 +88,53 @@ func TestTrimSpaceEachLineAndPad(t *testing.T) {
 	`
 	assert.Equal(t, "  \n  foo\n  bar baz\n  \n", trimSpaceEachLineAndPad(foo, "  "))
 }
+
+func TestCronSpec(t *testing.T) {
+
+	expectAccept := []string{
+		`"* * * * *"`,
+		`"0-10 * * * *"`,
+		`"* 0-5,8,12 * * *"`,
+	}
+
+	expectFail := []string{
+		`* * * *`,
+		``,
+		`23`,
+		`"@reboot"`,
+		`"@every 1h30m"`,
+		`"@daily"`,
+		`* * * * * *`,
+	}
+
+	for _, input := range expectAccept {
+		t.Run(input, func(t *testing.T) {
+			s := fmt.Sprintf("spec: %s\n", input)
+			var v struct {
+				Spec CronSpec
+			}
+			v.Spec.Schedule = nil
+			t.Logf("input:\n%s", s)
+			err := yaml.UnmarshalStrict([]byte(s), &v)
+			t.Logf("error: %T %s", err, err)
+			require.NoError(t, err)
+			require.NotNil(t, v.Spec.Schedule)
+		})
+	}
+
+	for _, input := range expectFail {
+		t.Run(input, func(t *testing.T) {
+			s := fmt.Sprintf("spec: %s\n", input)
+			var v struct {
+				Spec CronSpec
+			}
+			v.Spec.Schedule = nil
+			t.Logf("input: %q", s)
+			err := yaml.UnmarshalStrict([]byte(s), &v)
+			t.Logf("error: %T %s", err, err)
+			require.Error(t, err)
+			require.Nil(t, v.Spec.Schedule)
+		})
+	}
+
+}

config/samples/bandwidth_limit.yml

@@ -0,0 +1,41 @@
+
+jobs:
+  - type: sink
+    name: "limited_sink"
+    root_fs: "fs0"
+    recv:
+      bandwidth_limit:
+        max: 12345 B
+    serve:
+      type: local
+      listener_name: localsink
+
+  - type: push
+    name: "limited_push"
+    connect:
+      type: local
+      listener_name: localsink
+      client_identity: local_backup
+    filesystems: {
+      "root<": true,
+    }
+    send:
+      bandwidth_limit:
+        max: 54321 B
+        bucket_capacity: 1024 B
+    snapshotting:
+      type: manual
+    pruning:
+      keep_sender:
+        - type: last_n
+          count: 1
+      keep_receiver:
+        - type: last_n
+          count: 1
+
+  - type: sink
+    name: "nolimit_sink"
+    root_fs: "fs1"
+    serve:
+      type: local
+      listener_name: localsink

config/samples/quickstart_backup_to_external_disk.yml

@@ -5,7 +5,7 @@
 # quick start section which inlines this example.
 #
 # CUSTOMIZATIONS YOU WILL LIKELY WANT TO APPLY:
-# - adjust the name of the production pool `system` in the `filesystems` filter of jobs `snapjob` and `push_to_derive`
+# - adjust the name of the production pool `system` in the `filesystems` filter of jobs `snapjob` and `push_to_drive`
 # - adjust the name of the backup pool `backuppool` in the `backuppool_sink` job
 # - adjust the occurences of `myhostname` to the name of the system you are backing up (cannot be easily changed once you start replicating)
 # - make sure the `zrepl_` prefix is not being used by any other zfs tools you might have installed (it likely isn't)
@@ -85,4 +85,4 @@ jobs:
   root_fs: "backuppool/zrepl/sink"
   serve:
     type: local
-    listener_name: backuppool_sink
+    listener_name: backuppool_sink

config/samples/quickstart_continuous_server_backup_sender.yml

@@ -9,8 +9,8 @@ jobs:
     key:  /etc/zrepl/prod.key
     server_cn: "backups"
   filesystems: {
-    "zroot/var/db": true,
-    "zroot/usr/home<": true,
+    "zroot<": true,
+    "zroot/var/tmp<": false,
     "zroot/usr/home/paranoid": false
   }
   snapshotting:

config/samples/quickstart_fan_out_replication_source.yml

@@ -0,0 +1,59 @@
+jobs:
+# Separate job for snapshots and pruning
+- name: snapshots
+  type: snap
+  filesystems:
+    'tank<': true # all filesystems
+  snapshotting:
+    type: periodic
+    prefix: zrepl_
+    interval: 10m
+  pruning:
+    keep:
+      # Keep non-zrepl snapshots
+      - type: regex
+        negate: true
+        regex: '^zrepl_'
+      # Time-based snapshot retention
+      - type: grid
+        grid: 1x1h(keep=all) | 24x1h | 30x1d | 12x30d
+        regex: '^zrepl_'
+
+# Source job for target B
+- name: target_b
+  type: source
+  serve:
+    type: tls
+    listen: :8888
+    ca: /etc/zrepl/b.example.com.crt
+    cert: /etc/zrepl/a.example.com.crt
+    key: /etc/zrepl/a.example.com.key
+    client_cns:
+      - b.example.com
+  filesystems:
+    'tank<': true # all filesystems
+  # Snapshots are handled by the separate snap job
+  snapshotting:
+    type: manual
+
+# Source job for target C
+- name: target_c
+  type: source
+  serve:
+    type: tls
+    listen: :8889
+    ca: /etc/zrepl/c.example.com.crt
+    cert: /etc/zrepl/a.example.com.crt
+    key: /etc/zrepl/a.example.com.key
+    client_cns:
+      - c.example.com
+  filesystems:
+    'tank<': true # all filesystems
+  # Snapshots are handled by the separate snap job
+  snapshotting:
+    type: manual
+
+# Source jobs for remaining targets. Each one should listen on a different port
+# and reference the correct certificate and client CN.
+# - name: target_c
+#   ...

config/samples/quickstart_fan_out_replication_target.yml

@@ -0,0 +1,30 @@
+jobs:
+# Pull from source server A
+- name: source_a
+  type: pull
+  connect:
+    type: tls
+    # Use the correct port for this specific client (eg. B is 8888, C is 8889, etc.)
+    address: a.example.com:8888
+    ca: /etc/zrepl/a.example.com.crt
+    # Use the correct key pair for this specific client
+    cert: /etc/zrepl/b.example.com.crt
+    key: /etc/zrepl/b.example.com.key
+    server_cn: a.example.com
+  root_fs: pool0/backup
+  interval: 10m
+  pruning:
+    keep_sender:
+      # Source does the pruning in its snap job
+      - type: regex
+        regex: '.*'
+    # Receiver-side pruning can be configured as desired on each target server
+    keep_receiver:
+      # Keep non-zrepl snapshots
+      - type: regex
+        negate: true
+        regex: '^zrepl_'
+      # Time-based snapshot retention
+      - type: grid
+        grid: 1x1h(keep=all) | 24x1h | 30x1d | 12x30d
+        regex: '^zrepl_'

config/samples/snap_cron.yml

@@ -0,0 +1,14 @@
+jobs:
+- name: snapjob
+  type: snap
+  filesystems: {
+    "tank<": true,
+  }
+  snapshotting:
+    type: cron
+    prefix: zrepl_snapjob_
+    cron: "*/5 * * * *"
+  pruning:
+    keep:
+      - type: last_n
+        count: 60

daemon/control.go

@@ -8,6 +8,7 @@ import (
 	"io"
 	"net"
 	"net/http"
+	"os"
 	"time"
 
 	"github.com/pkg/errors"
@@ -124,8 +125,9 @@ func (j *controlJob) Run(ctx context.Context) {
 			s := Status{
 				Jobs: jobs,
 				Global: GlobalStatus{
-					ZFSCmds:  globalZFS,
-					Envconst: envconstReport,
+					ZFSCmds:   globalZFS,
+					Envconst:  envconstReport,
+					OsEnviron: os.Environ(),
 				}}
 			return s, nil
 		}})
@@ -156,8 +158,8 @@ func (j *controlJob) Run(ctx context.Context) {
 	server := http.Server{
 		Handler: mux,
 		// control socket is local, 1s timeout should be more than sufficient, even on a loaded system
-		WriteTimeout: 1 * time.Second,
-		ReadTimeout:  1 * time.Second,
+		WriteTimeout: envconst.Duration("ZREPL_DAEMON_CONTROL_SERVER_WRITE_TIMEOUT", 1*time.Second),
+		ReadTimeout:  envconst.Duration("ZREPL_DAEMON_CONTROL_SERVER_READ_TIMEOUT", 1*time.Second),
 	}
 
 outer:

daemon/daemon.go

@@ -51,7 +51,7 @@ func Run(ctx context.Context, conf *config.Config) error {
 	}
 	outlets.Add(newPrometheusLogOutlet(), logger.Debug)
 
-	confJobs, err := job.JobsFromConfig(conf)
+	confJobs, err := job.JobsFromConfig(conf, config.ParseFlagsNone)
 	if err != nil {
 		return errors.Wrap(err, "cannot build jobs from config")
 	}
@@ -160,8 +160,9 @@ type Status struct {
 }
 
 type GlobalStatus struct {
-	ZFSCmds  *zfscmd.Report
-	Envconst *envconst.Report
+	ZFSCmds   *zfscmd.Report
+	Envconst  *envconst.Report
+	OsEnviron []string
 }
 
 func (s *jobs) status() map[string]*job.Status {

daemon/filters/fsmapfilter.go

@@ -160,6 +160,14 @@ func (m DatasetMapFilter) Filter(p *zfs.DatasetPath) (pass bool, err error) {
 	return
 }
 
+func (m DatasetMapFilter) UserSpecifiedDatasets() (datasets zfs.UserSpecifiedDatasetsSet) {
+	datasets = make(zfs.UserSpecifiedDatasetsSet)
+	for i := range m.entries {
+		datasets[m.entries[i].path.ToString()] = true
+	}
+	return
+}
+
 // Construct a new filter-only DatasetMapFilter from a mapping
 // The new filter allows exactly those paths that were not forbidden by the mapping.
 func (m DatasetMapFilter) InvertedFilter() (inv *DatasetMapFilter, err error) {

daemon/hooks/hook_docs.go

@@ -5,7 +5,7 @@
 //
 // This package also provides all supported hook type implementations and abstractions around them.
 //
-// Use For Other Kinds Of ExpectStepReports
+// # Use For Other Kinds Of ExpectStepReports
 //
 // This package REQUIRES REFACTORING before it can be used for other activities than snapshots, e.g. pre- and post-replication:
 //
@@ -15,7 +15,7 @@
 // The hook implementations should move out of this package.
 // However, there is a lot of tight coupling which to untangle isn't worth it ATM.
 //
-// How This Package Is Used By Package Snapper
+// # How This Package Is Used By Package Snapper
 //
 // Deserialize a config.List using ListFromConfig().
 // Then it MUST filter the list to only contain hooks for a particular filesystem using
@@ -30,5 +30,4 @@
 // Command hooks make it available in the environment variable ZREPL_DRYRUN.
 //
 // Plan.Report() can be called while Plan.Run() is executing to give an overview of plan execution progress (future use in "zrepl status").
-//
 package hooks

daemon/hooks/hook_type_command.go

@@ -93,7 +93,14 @@ func (r *CommandHookReport) String() string {
 		cmdLine.WriteString(fmt.Sprintf("%s'%s'", sep, a))
 	}
 
-	return fmt.Sprintf("command hook invocation: \"%s\"", cmdLine.String()) // no %q to make copy-pastable
+	var msg string
+	if r.Err == nil {
+		msg = "command hook"
+	} else {
+		msg = fmt.Sprintf("command hook failed with %q", r.Err)
+	}
+
+	return fmt.Sprintf("%s: \"%s\"", msg, cmdLine.String()) // no %q to make copy-pastable
 }
 func (r *CommandHookReport) Error() string {
 	if r.Err == nil {

daemon/hooks/hook_type_mysql_lock_tables.go

@@ -17,19 +17,22 @@ import (
 	"github.com/zrepl/zrepl/zfs"
 )
 
+// Hook to implement the following recommmendation from MySQL docs
 // https://dev.mysql.com/doc/mysql-backup-excerpt/5.7/en/backup-methods.html
 //
-// Making Backups Using a File System Snapshot:
+//	Making Backups Using a File System Snapshot:
 //
-//  If you are using a Veritas file system, you can make a backup like this:
+//	If you are using a Veritas file system, you can make a backup like this:
 //
-//    	From a client program, execute FLUSH TABLES WITH READ LOCK.
-//    	From another shell, execute mount vxfs snapshot.
-//    	From the first client, execute UNLOCK TABLES.
-//    	Copy files from the snapshot.
-//    	Unmount the snapshot.
+//	   	From a client program, execute FLUSH TABLES WITH READ LOCK.
+//	   	From another shell, execute mount vxfs snapshot.
+//	   	From the first client, execute UNLOCK TABLES.
+//	   	Copy files from the snapshot.
+//	   	Unmount the snapshot.
 //
-//	Similar snapshot capabilities may be available in other file systems, such as LVM or ZFS.
+//		Similar snapshot capabilities may be available in other file systems, such as LVM or ZFS.
+//
+
 type MySQLLockTables struct {
 	errIsFatal  bool
 	connector   sqldriver.Connector

daemon/hooks/hooks_test.go

@@ -161,7 +161,7 @@ jobs:
 					ExpectedEdge: hooks.Pre,
 					ExpectStatus: hooks.StepErr,
 					OutputTest:   containsTest(fmt.Sprintf("TEST ERROR pre_testing %s@%s", testFSName, testSnapshotName)),
-					ErrorTest:    regexpTest("^command hook invocation.*exit status 1$"),
+					ErrorTest:    regexpTest("^command hook failed.*exit status 1$"),
 				},
 				expectStep{ExpectedEdge: hooks.Callback, ExpectStatus: hooks.StepOk},
 				expectStep{
@@ -185,7 +185,7 @@ jobs:
 					ExpectedEdge: hooks.Pre,
 					ExpectStatus: hooks.StepErr,
 					OutputTest:   containsTest(fmt.Sprintf("TEST ERROR pre_testing %s@%s", testFSName, testSnapshotName)),
-					ErrorTest:    regexpTest("^command hook invocation.*exit status 1$"),
+					ErrorTest:    regexpTest("^command hook failed.*exit status 1$"),
 				},
 				expectStep{
 					ExpectedEdge: hooks.Pre,
@@ -234,7 +234,7 @@ jobs:
 					ExpectedEdge: hooks.Post,
 					ExpectStatus: hooks.StepErr,
 					OutputTest:   containsTest(fmt.Sprintf("TEST ERROR post_testing %s@%s", testFSName, testSnapshotName)),
-					ErrorTest:    regexpTest("^command hook invocation.*exit status 1$"),
+					ErrorTest:    regexpTest("^command hook failed.*exit status 1$"),
 				},
 			},
 		},
@@ -267,7 +267,7 @@ jobs:
 					ExpectedEdge: hooks.Pre,
 					ExpectStatus: hooks.StepErr,
 					OutputTest:   containsTest(fmt.Sprintf("TEST ERROR pre_testing %s@%s", testFSName, testSnapshotName)),
-					ErrorTest:    regexpTest("^command hook invocation.*exit status 1$"),
+					ErrorTest:    regexpTest("^command hook failed.*exit status 1$"),
 				},
 				expectStep{ExpectedEdge: hooks.Callback, ExpectStatus: hooks.StepOk},
 				expectStep{
@@ -295,7 +295,7 @@ jobs:
 					ExpectedEdge: hooks.Pre,
 					ExpectStatus: hooks.StepErr,
 					OutputTest:   containsTest(fmt.Sprintf("TEST ERROR pre_testing %s@%s", testFSName, testSnapshotName)),
-					ErrorTest:    regexpTest("^command hook invocation.*exit status 1$"),
+					ErrorTest:    regexpTest("^command hook failed.*exit status 1$"),
 				},
 				expectStep{ExpectedEdge: hooks.Callback, ExpectStatus: hooks.StepOk},
 				expectStep{

daemon/job/active.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/zrepl/zrepl/config"
 	"github.com/zrepl/zrepl/daemon/job/reset"
+	"github.com/zrepl/zrepl/daemon/job/trigger"
 	"github.com/zrepl/zrepl/daemon/job/wakeup"
 	"github.com/zrepl/zrepl/daemon/pruner"
 	"github.com/zrepl/zrepl/daemon/snapper"
@@ -42,6 +43,9 @@ type ActiveSide struct {
 	promPruneSecs         *prometheus.HistogramVec // labels: prune_side
 	promBytesReplicated   *prometheus.CounterVec   // labels: filesystem
 	promReplicationErrors prometheus.Gauge
+	promLastSuccessful    prometheus.Gauge
+
+	triggers *trigger.Triggers
 
 	tasksMtx sync.Mutex
 	tasks    activeSideTasks
@@ -89,7 +93,7 @@ type activeMode interface {
 	SenderReceiver() (logic.Sender, logic.Receiver)
 	Type() Type
 	PlannerPolicy() logic.PlannerPolicy
-	RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{})
+	RunPeriodic(ctx context.Context, wakeReplication *trigger.Manual)
 	SnapperReport() *snapper.Report
 	ResetConnectBackoff()
 }
@@ -100,7 +104,7 @@ type modePush struct {
 	receiver      *rpc.Client
 	senderConfig  *endpoint.SenderConfig
 	plannerPolicy *logic.PlannerPolicy
-	snapper       *snapper.PeriodicOrManual
+	snapper       snapper.Snapper
 }
 
 func (m *modePush) ConnectEndpoints(ctx context.Context, connecter transport.Connecter) {
@@ -131,12 +135,13 @@ func (m *modePush) Type() Type { return TypePush }
 
 func (m *modePush) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
 
-func (m *modePush) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}) {
-	m.snapper.Run(ctx, wakeUpCommon)
+func (m *modePush) RunPeriodic(ctx context.Context, trigger *trigger.Manual) {
+	m.snapper.Run(ctx, trigger)
 }
 
 func (m *modePush) SnapperReport() *snapper.Report {
-	return m.snapper.Report()
+	r := m.snapper.Report()
+	return &r
 }
 
 func (m *modePush) ResetConnectBackoff() {
@@ -161,8 +166,13 @@ func modePushFromConfig(g *config.Global, in *config.PushJob, jobID endpoint.Job
 		return nil, errors.Wrap(err, "field `replication`")
 	}
 
+	conflictResolution, err := logic.ConflictResolutionFromConfig(in.ConflictResolution)
+	if err != nil {
+		return nil, errors.Wrap(err, "field `conflict_resolution`")
+	}
+
 	m.plannerPolicy = &logic.PlannerPolicy{
-		EncryptedSend:             logic.TriFromBool(in.Send.Encrypted),
+		ConflictResolution:        conflictResolution,
 		ReplicationConfig:         replicationConfig,
 		SizeEstimationConcurrency: in.Replication.Concurrency.SizeEstimates,
 	}
@@ -214,7 +224,7 @@ func (*modePull) Type() Type { return TypePull }
 
 func (m *modePull) PlannerPolicy() logic.PlannerPolicy { return *m.plannerPolicy }
 
-func (m *modePull) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}) {
+func (m *modePull) RunPeriodic(ctx context.Context, wakeReplication *trigger.Manual) {
 	if m.interval.Manual {
 		GetLogger(ctx).Info("manual pull configured, periodic pull disabled")
 		// "waiting for wakeups" is printed in common ActiveSide.do
@@ -225,14 +235,7 @@ func (m *modePull) RunPeriodic(ctx context.Context, wakeUpCommon chan<- struct{}
 	for {
 		select {
 		case <-t.C:
-			select {
-			case wakeUpCommon <- struct{}{}:
-			default:
-				GetLogger(ctx).
-					WithField("pull_interval", m.interval).
-					Warn("pull job took longer than pull interval")
-				wakeUpCommon <- struct{}{} // block anyways, to queue up the wakeup
-			}
+			wakeReplication.Fire()
 		case <-ctx.Done():
 			return
 		}
@@ -260,8 +263,13 @@ func modePullFromConfig(g *config.Global, in *config.PullJob, jobID endpoint.Job
 		return nil, errors.Wrap(err, "field `replication`")
 	}
 
+	conflictResolution, err := logic.ConflictResolutionFromConfig(in.ConflictResolution)
+	if err != nil {
+		return nil, errors.Wrap(err, "field `conflict_resolution`")
+	}
+
 	m.plannerPolicy = &logic.PlannerPolicy{
-		EncryptedSend:             logic.DontCare,
+		ConflictResolution:        conflictResolution,
 		ReplicationConfig:         replicationConfig,
 		SizeEstimationConcurrency: in.Replication.Concurrency.SizeEstimates,
 	}
@@ -287,7 +295,7 @@ func replicationDriverConfigFromConfig(in *config.Replication) (c driver.Config,
 	return c, err
 }
 
-func activeSide(g *config.Global, in *config.ActiveJob, configJob interface{}) (j *ActiveSide, err error) {
+func activeSide(g *config.Global, in *config.ActiveJob, configJob interface{}, parseFlags config.ParseFlags) (j *ActiveSide, err error) {
 
 	j = &ActiveSide{}
 	j.name, err = endpoint.MakeJobID(in.Name)
@@ -321,7 +329,6 @@ func activeSide(g *config.Global, in *config.ActiveJob, configJob interface{}) (
 		Help:        "number of bytes replicated from sender to receiver per filesystem",
 		ConstLabels: prometheus.Labels{"zrepl_job": j.name.String()},
 	}, []string{"filesystem"})
-
 	j.promReplicationErrors = prometheus.NewGauge(prometheus.GaugeOpts{
 		Namespace:   "zrepl",
 		Subsystem:   "replication",
@@ -329,8 +336,15 @@ func activeSide(g *config.Global, in *config.ActiveJob, configJob interface{}) (
 		Help:        "number of filesystems that failed replication in the latest replication attempt, or -1 if the job failed before enumerating the filesystems",
 		ConstLabels: prometheus.Labels{"zrepl_job": j.name.String()},
 	})
+	j.promLastSuccessful = prometheus.NewGauge(prometheus.GaugeOpts{
+		Namespace:   "zrepl",
+		Subsystem:   "replication",
+		Name:        "last_successful",
+		Help:        "timestamp of last successful replication",
+		ConstLabels: prometheus.Labels{"zrepl_job": j.name.String()},
+	})
 
-	j.connecter, err = fromconfig.ConnecterFromConfig(g, in.Connect)
+	j.connecter, err = fromconfig.ConnecterFromConfig(g, in.Connect, parseFlags)
 	if err != nil {
 		return nil, errors.Wrap(err, "cannot build client")
 	}
@@ -352,6 +366,11 @@ func activeSide(g *config.Global, in *config.ActiveJob, configJob interface{}) (
 		return nil, errors.Wrap(err, "cannot build replication driver config")
 	}
 
+	j.triggers, err = trigger.FromConfig(in.Replication.Triggers)
+	if err != nil {
+		return nil, errors.Wrap(err, "cannot build triggers")
+	}
+
 	return j, nil
 }
 
@@ -360,6 +379,7 @@ func (j *ActiveSide) RegisterMetrics(registerer prometheus.Registerer) {
 	registerer.MustRegister(j.promPruneSecs)
 	registerer.MustRegister(j.promBytesReplicated)
 	registerer.MustRegister(j.promReplicationErrors)
+	registerer.MustRegister(j.promLastSuccessful)
 }
 
 func (j *ActiveSide) Name() string { return j.name.String() }
@@ -425,12 +445,17 @@ func (j *ActiveSide) Run(ctx context.Context) {
 
 	defer log.Info("job exiting")
 
-	periodicDone := make(chan struct{})
 	ctx, cancel := context.WithCancel(ctx)
 	defer cancel()
-	periodicCtx, endTask := trace.WithTask(ctx, "periodic")
+
+	periodCtx, endTask := trace.WithTask(ctx, "periodic")
+	defer endTask()
+	go j.mode.RunPeriodic(periodCtx, periodicTrigger)
+
+	wakeupTrigger := wakeup.Trigger(ctx)
+
+	triggered, endTask := j.triggers.Spawn(ctx, []*trigger.Trigger{periodicTrigger, wakeupTrigger})
 	defer endTask()
-	go j.mode.RunPeriodic(periodicCtx, periodicDone)
 
 	invocationCount := 0
 outer:
@@ -440,10 +465,15 @@ outer:
 		case <-ctx.Done():
 			log.WithError(ctx.Err()).Info("context")
 			break outer
-
-		case <-wakeup.Wait(ctx):
-			j.mode.ResetConnectBackoff()
-		case <-periodicDone:
+		case trigger := <-triggered:
+			log :=
+				log.WithField("trigger_id", trigger.ID())
+			log.Info("triggered")
+			switch trigger {
+			case wakeupTrigger:
+				log.Info("trigger is wakeup command, resetting connection backoff")
+				j.mode.ResetConnectBackoff()
+			}
 		}
 		invocationCount++
 		invocationCtx, endSpan := trace.WithSpan(ctx, fmt.Sprintf("invocation-%d", invocationCount))
@@ -494,7 +524,11 @@ func (j *ActiveSide) do(ctx context.Context) {
 		repCancel()   // always cancel to free up context resources
 
 		replicationReport := j.tasks.replicationReport()
-		j.promReplicationErrors.Set(float64(replicationReport.GetFailedFilesystemsCountInLatestAttempt()))
+		var numErrors = replicationReport.GetFailedFilesystemsCountInLatestAttempt()
+		j.promReplicationErrors.Set(float64(numErrors))
+		if numErrors == 0 {
+			j.promLastSuccessful.SetToCurrentTime()
+		}
 
 		endSpan()
 	}

daemon/job/build_jobs.go

@@ -8,12 +8,13 @@ import (
 	"github.com/pkg/errors"
 
 	"github.com/zrepl/zrepl/config"
+	"github.com/zrepl/zrepl/util/bandwidthlimit"
 )
 
-func JobsFromConfig(c *config.Config) ([]Job, error) {
+func JobsFromConfig(c *config.Config, parseFlags config.ParseFlags) ([]Job, error) {
 	js := make([]Job, len(c.Jobs))
 	for i := range c.Jobs {
-		j, err := buildJob(c.Global, c.Jobs[i])
+		j, err := buildJob(c.Global, c.Jobs[i], parseFlags)
 		if err != nil {
 			return nil, err
 		}
@@ -23,37 +24,22 @@ func JobsFromConfig(c *config.Config) ([]Job, error) {
 		js[i] = j
 	}
 
-	// receiving-side root filesystems must not overlap
-	{
-		rfss := make([]string, 0, len(js))
-		for _, j := range js {
-			jrfs, ok := j.OwnedDatasetSubtreeRoot()
-			if !ok {
-				continue
-			}
-			rfss = append(rfss, jrfs.ToString())
-		}
-		if err := validateReceivingSidesDoNotOverlap(rfss); err != nil {
-			return nil, err
-		}
-	}
-
 	return js, nil
 }
 
-func buildJob(c *config.Global, in config.JobEnum) (j Job, err error) {
+func buildJob(c *config.Global, in config.JobEnum, parseFlags config.ParseFlags) (j Job, err error) {
 	cannotBuildJob := func(e error, name string) (Job, error) {
 		return nil, errors.Wrapf(e, "cannot build job %q", name)
 	}
 	// FIXME prettify this
 	switch v := in.Ret.(type) {
 	case *config.SinkJob:
-		j, err = passiveSideFromConfig(c, &v.PassiveJob, v)
+		j, err = passiveSideFromConfig(c, &v.PassiveJob, v, parseFlags)
 		if err != nil {
 			return cannotBuildJob(err, v.Name)
 		}
 	case *config.SourceJob:
-		j, err = passiveSideFromConfig(c, &v.PassiveJob, v)
+		j, err = passiveSideFromConfig(c, &v.PassiveJob, v, parseFlags)
 		if err != nil {
 			return cannotBuildJob(err, v.Name)
 		}
@@ -63,12 +49,12 @@ func buildJob(c *config.Global, in config.JobEnum) (j Job, err error) {
 			return cannotBuildJob(err, v.Name)
 		}
 	case *config.PushJob:
-		j, err = activeSide(c, &v.ActiveJob, v)
+		j, err = activeSide(c, &v.ActiveJob, v, parseFlags)
 		if err != nil {
 			return cannotBuildJob(err, v.Name)
 		}
 	case *config.PullJob:
-		j, err = activeSide(c, &v.ActiveJob, v)
+		j, err = activeSide(c, &v.ActiveJob, v, parseFlags)
 		if err != nil {
 			return cannotBuildJob(err, v.Name)
 		}
@@ -107,3 +93,13 @@ func validateReceivingSidesDoNotOverlap(receivingRootFSs []string) error {
 	}
 	return nil
 }
+
+func buildBandwidthLimitConfig(in *config.BandwidthLimit) (c bandwidthlimit.Config, _ error) {
+	if in.Max.ToBytes() > 0 && int64(in.Max.ToBytes()) == 0 {
+		return c, fmt.Errorf("bandwidth limit `max` is too small, must at least specify one byte")
+	}
+	return bandwidthlimit.Config{
+		Max:            int64(in.Max.ToBytes()),
+		BucketCapacity: int64(in.BucketCapacity.ToBytes()),
+	}, nil
+}

daemon/job/build_jobs_sendrecvoptions.go

@@ -22,7 +22,12 @@ func buildSenderConfig(in SendingJobConfig, jobID endpoint.JobID) (*endpoint.Sen
 		return nil, errors.Wrap(err, "cannot build filesystem filter")
 	}
 	sendOpts := in.GetSendOptions()
-	return &endpoint.SenderConfig{
+	bwlim, err := buildBandwidthLimitConfig(sendOpts.BandwidthLimit)
+	if err != nil {
+		return nil, errors.Wrap(err, "cannot build bandwith limit config")
+	}
+
+	sc := &endpoint.SenderConfig{
 		FSF:   fsf,
 		JobID: jobID,
 
@@ -34,7 +39,15 @@ func buildSenderConfig(in SendingJobConfig, jobID endpoint.JobID) (*endpoint.Sen
 		SendCompressed:       sendOpts.Compressed,
 		SendEmbeddedData:     sendOpts.EmbeddedData,
 		SendSaved:            sendOpts.Saved,
-	}, nil
+
+		BandwidthLimit: bwlim,
+	}
+
+	if err := sc.Validate(); err != nil {
+		return nil, errors.Wrap(err, "cannot build sender config")
+	}
+
+	return sc, nil
 }
 
 type ReceivingJobConfig interface {
@@ -53,6 +66,22 @@ func buildReceiverConfig(in ReceivingJobConfig, jobID endpoint.JobID) (rc endpoi
 	}
 
 	recvOpts := in.GetRecvOptions()
+
+	bwlim, err := buildBandwidthLimitConfig(recvOpts.BandwidthLimit)
+	if err != nil {
+		return rc, errors.Wrap(err, "cannot build bandwith limit config")
+	}
+
+	placeholderEncryption, err := endpoint.PlaceholderCreationEncryptionPropertyString(recvOpts.Placeholder.Encryption)
+	if err != nil {
+		options := []string{}
+		for _, v := range endpoint.PlaceholderCreationEncryptionPropertyValues() {
+			options = append(options, endpoint.PlaceholderCreationEncryptionProperty(v).String())
+		}
+		return rc, errors.Errorf("placeholder encryption value %q is invalid, must be one of %s",
+			recvOpts.Placeholder.Encryption, options)
+	}
+
 	rc = endpoint.ReceiverConfig{
 		JobID:                      jobID,
 		RootWithoutClientComponent: rootFs,
@@ -60,6 +89,10 @@ func buildReceiverConfig(in ReceivingJobConfig, jobID endpoint.JobID) (rc endpoi
 
 		InheritProperties:  recvOpts.Properties.Inherit,
 		OverrideProperties: recvOpts.Properties.Override,
+
+		BandwidthLimit: bwlim,
+
+		PlaceholderEncryption: placeholderEncryption,
 	}
 	if err := rc.Validate(); err != nil {
 		return rc, errors.Wrap(err, "cannot build receiver config")

daemon/job/build_jobs_test.go

@@ -11,7 +11,6 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/zrepl/zrepl/config"
-	"github.com/zrepl/zrepl/transport/tls"
 )
 
 func TestValidateReceivingSidesDoNotOverlap(t *testing.T) {
@@ -96,7 +95,7 @@ jobs:
 			conf, err := config.ParseConfigBytes([]byte(fill(c.jobName)))
 			require.NoError(t, err, "not expecting yaml-config to know about job ids")
 			require.NotNil(t, conf)
-			jobs, err := JobsFromConfig(conf)
+			jobs, err := JobsFromConfig(conf, config.ParseFlagsNone)
 
 			if c.valid {
 				assert.NoError(t, err)
@@ -119,6 +118,14 @@ func TestSampleConfigsAreBuiltWithoutErrors(t *testing.T) {
 		t.Errorf("glob failed: %+v", err)
 	}
 
+	type additionalCheck struct {
+		state int
+		test  func(t *testing.T, jobs []Job)
+	}
+	additionalChecks := map[string]*additionalCheck{
+		"bandwidth_limit.yml": {test: testSampleConfig_BandwidthLimit},
+	}
+
 	for _, p := range paths {
 
 		if path.Ext(p) != ".yml" {
@@ -126,23 +133,78 @@ func TestSampleConfigsAreBuiltWithoutErrors(t *testing.T) {
 			continue
 		}
 
+		filename := path.Base(p)
+		t.Logf("checking for presence additonal checks for file %q", filename)
+		additionalCheck := additionalChecks[filename]
+		if additionalCheck == nil {
+			t.Logf("no additional checks")
+		} else {
+			t.Logf("additional check present")
+			additionalCheck.state = 1
+		}
+
 		t.Run(p, func(t *testing.T) {
 			c, err := config.ParseConfig(p)
 			if err != nil {
-				t.Errorf("error parsing %s:\n%+v", p, err)
+				t.Fatalf("error parsing %s:\n%+v", p, err)
 			}
 
 			t.Logf("file: %s", p)
 			t.Log(pretty.Sprint(c))
 
-			tls.FakeCertificateLoading(t)
-			jobs, err := JobsFromConfig(c)
+			jobs, err := JobsFromConfig(c, config.ParseFlagsNoCertCheck)
 			t.Logf("jobs: %#v", jobs)
-			assert.NoError(t, err)
+			require.NoError(t, err)
+
+			if additionalCheck != nil {
+				additionalCheck.test(t, jobs)
+				additionalCheck.state = 2
+			}
 		})
 
 	}
 
+	for basename, c := range additionalChecks {
+		if c.state == 0 {
+			panic("univisited additional check " + basename)
+		}
+	}
+
+}
+
+func testSampleConfig_BandwidthLimit(t *testing.T, jobs []Job) {
+	require.Len(t, jobs, 3)
+
+	{
+		limitedSink, ok := jobs[0].(*PassiveSide)
+		require.True(t, ok, "%T", jobs[0])
+		limitedSinkMode, ok := limitedSink.mode.(*modeSink)
+		require.True(t, ok, "%T", limitedSink)
+
+		assert.Equal(t, int64(12345), limitedSinkMode.receiverConfig.BandwidthLimit.Max)
+		assert.Equal(t, int64(1<<17), limitedSinkMode.receiverConfig.BandwidthLimit.BucketCapacity)
+	}
+
+	{
+		limitedPush, ok := jobs[1].(*ActiveSide)
+		require.True(t, ok, "%T", jobs[1])
+		limitedPushMode, ok := limitedPush.mode.(*modePush)
+		require.True(t, ok, "%T", limitedPush)
+
+		assert.Equal(t, int64(54321), limitedPushMode.senderConfig.BandwidthLimit.Max)
+		assert.Equal(t, int64(1024), limitedPushMode.senderConfig.BandwidthLimit.BucketCapacity)
+	}
+
+	{
+		unlimitedSink, ok := jobs[2].(*PassiveSide)
+		require.True(t, ok, "%T", jobs[2])
+		unlimitedSinkMode, ok := unlimitedSink.mode.(*modeSink)
+		require.True(t, ok, "%T", unlimitedSink)
+
+		max := unlimitedSinkMode.receiverConfig.BandwidthLimit.Max
+		assert.Less(t, max, int64(0), max, "unlimited mode <=> negative value for .Max, see bandwidthlimit.Config")
+	}
+
 }
 
 func TestReplicationOptions(t *testing.T) {
@@ -235,7 +297,7 @@ jobs:
 			t.Logf("testing config:\n%s", cstr)
 			c, err := config.ParseConfigBytes([]byte(cstr))
 			require.NoError(t, err)
-			jobs, err := JobsFromConfig(c)
+			jobs, err := JobsFromConfig(c, config.ParseFlagsNone)
 			if ts.expectOk != nil {
 				require.NoError(t, err)
 				require.NotNil(t, c)

daemon/job/passive.go

@@ -58,7 +58,7 @@ func modeSinkFromConfig(g *config.Global, in *config.SinkJob, jobID endpoint.Job
 
 type modeSource struct {
 	senderConfig *endpoint.SenderConfig
-	snapper      *snapper.PeriodicOrManual
+	snapper      snapper.Snapper
 }
 
 func modeSourceFromConfig(g *config.Global, in *config.SourceJob, jobID endpoint.JobID) (m *modeSource, err error) {
@@ -88,10 +88,11 @@ func (m *modeSource) RunPeriodic(ctx context.Context) {
 }
 
 func (m *modeSource) SnapperReport() *snapper.Report {
-	return m.snapper.Report()
+	r := m.snapper.Report()
+	return &r
 }
 
-func passiveSideFromConfig(g *config.Global, in *config.PassiveJob, configJob interface{}) (s *PassiveSide, err error) {
+func passiveSideFromConfig(g *config.Global, in *config.PassiveJob, configJob interface{}, parseFlags config.ParseFlags) (s *PassiveSide, err error) {
 
 	s = &PassiveSide{}
 
@@ -110,7 +111,7 @@ func passiveSideFromConfig(g *config.Global, in *config.PassiveJob, configJob in
 		return nil, err // no wrapping necessary
 	}
 
-	if s.listen, err = fromconfig.ListenerFactoryFromConfig(g, in.Serve); err != nil {
+	if s.listen, err = fromconfig.ListenerFactoryFromConfig(g, in.Serve, parseFlags); err != nil {
 		return nil, errors.Wrap(err, "cannot build listener factory")
 	}
 

daemon/job/snapjob.go

@@ -10,10 +10,12 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/zrepl/zrepl/daemon/logging/trace"
+	"github.com/zrepl/zrepl/util/bandwidthlimit"
 	"github.com/zrepl/zrepl/util/nodefault"
 
 	"github.com/zrepl/zrepl/config"
 	"github.com/zrepl/zrepl/daemon/filters"
+	"github.com/zrepl/zrepl/daemon/job/trigger"
 	"github.com/zrepl/zrepl/daemon/job/wakeup"
 	"github.com/zrepl/zrepl/daemon/pruner"
 	"github.com/zrepl/zrepl/daemon/snapper"
@@ -25,7 +27,7 @@ import (
 type SnapJob struct {
 	name     endpoint.JobID
 	fsfilter zfs.DatasetFilter
-	snapper  *snapper.PeriodicOrManual
+	snapper  snapper.Snapper
 
 	prunerFactory *pruner.LocalPrunerFactory
 
@@ -85,7 +87,8 @@ func (j *SnapJob) Status() *Status {
 		s.Pruning = j.pruner.Report()
 	}
 	j.prunerMtx.Unlock()
-	s.Snapshotting = j.snapper.Report()
+	r := j.snapper.Report()
+	s.Snapshotting = &r
 	return &Status{Type: t, JobSpecific: s}
 }
 
@@ -102,12 +105,18 @@ func (j *SnapJob) Run(ctx context.Context) {
 
 	defer log.Info("job exiting")
 
-	periodicDone := make(chan struct{})
+	wakeupTrigger := wakeup.Trigger(ctx)
+
+	snapshottingTrigger := trigger.New("periodic")
 	ctx, cancel := context.WithCancel(ctx)
 	defer cancel()
 	periodicCtx, endTask := trace.WithTask(ctx, "snapshotting")
 	defer endTask()
-	go j.snapper.Run(periodicCtx, periodicDone)
+	go j.snapper.Run(periodicCtx, snapshottingTrigger)
+
+	triggers := trigger.Empty()
+	triggered, endTask := triggers.Spawn(ctx, []trigger.Trigger{snapshottingTrigger, wakeupTrigger})
+	defer endTask()
 
 	invocationCount := 0
 outer:
@@ -117,9 +126,7 @@ outer:
 		case <-ctx.Done():
 			log.WithError(ctx.Err()).Info("context")
 			break outer
-
-		case <-wakeup.Wait(ctx):
-		case <-periodicDone:
+		case <-triggered:
 		}
 		invocationCount++
 
@@ -136,7 +143,7 @@ outer:
 // TODO:
 // This is a work-around for the current package daemon/pruner
 // and package pruning.Snapshot limitation: they require the
-//  `Replicated` getter method be present, but obviously,
+// `Replicated` getter method be present, but obviously,
 // a local job like SnapJob can't deliver on that.
 // But the pruner.Pruner gives up on an FS if no replication
 // cursor is present, which is why this pruner returns the
@@ -146,7 +153,7 @@ type alwaysUpToDateReplicationCursorHistory struct {
 	target pruner.Target
 }
 
-var _ pruner.History = (*alwaysUpToDateReplicationCursorHistory)(nil)
+var _ pruner.Sender = (*alwaysUpToDateReplicationCursorHistory)(nil)
 
 func (h alwaysUpToDateReplicationCursorHistory) ReplicationCursor(ctx context.Context, req *pdu.ReplicationCursorReq) (*pdu.ReplicationCursorRes, error) {
 	fsvReq := &pdu.ListFilesystemVersionsReq{
@@ -179,8 +186,11 @@ func (j *SnapJob) doPrune(ctx context.Context) {
 	sender := endpoint.NewSender(endpoint.SenderConfig{
 		JobID: j.name,
 		FSF:   j.fsfilter,
-		// FIXME encryption setting is irrelevant for SnapJob because the endpoint is only used as pruner.Target
-		Encrypt: &nodefault.Bool{B: true},
+		// FIXME the following config fields are irrelevant for SnapJob
+		// because the endpoint is only used as pruner.Target.
+		// However, the implementation requires them to be set.
+		Encrypt:        &nodefault.Bool{B: true},
+		BandwidthLimit: bandwidthlimit.NoLimitConfig(),
 	})
 	j.prunerMtx.Lock()
 	j.pruner = j.prunerFactory.BuildLocalPruner(ctx, sender, alwaysUpToDateReplicationCursorHistory{sender})

daemon/job/trigger/cron.go

@@ -0,0 +1,23 @@
+package trigger
+
+import (
+	"context"
+
+	"github.com/robfig/cron/v3"
+)
+
+type Cron struct {
+	spec cron.Schedule
+}
+
+var _ Trigger = &Cron{}
+
+func NewCron(spec cron.Schedule) *Cron {
+	return &Cron{spec: spec}
+}
+
+func (t *Cron) ID() string { return "cron" }
+
+func (t *Cron) run(ctx context.Context, signal chan<- struct{}) {
+	panic("unimpl: extract from cron snapper")
+}

daemon/job/trigger/from_config.go

@@ -0,0 +1,30 @@
+package trigger
+
+import (
+	"fmt"
+
+	"github.com/zrepl/zrepl/config"
+)
+
+func FromConfig(in []*config.ReplicationTriggerEnum) (*Triggers, error) {
+	triggers := make([]Trigger, len(in))
+	for i, e := range in {
+		var t Trigger = nil
+		switch te := e.Ret.(type) {
+		case *config.ReplicationTriggerManual:
+			// not a trigger
+			t = NewManual("manual")
+		case *config.ReplicationTriggerPeriodic:
+			t = NewPeriodic(te.Interval.Duration())
+		case *config.ReplicationTriggerCron:
+			t = NewCron(te.Cron.Schedule)
+		default:
+			return nil, fmt.Errorf("unknown trigger type %T", te)
+		}
+		triggers[i] = t
+	}
+	return &Triggers{
+		spawned:  false,
+		triggers: triggers,
+	}, nil
+}

daemon/job/trigger/logger.go

@@ -0,0 +1,12 @@
+package trigger
+
+import (
+	"context"
+
+	"github.com/zrepl/zrepl/logger"
+)
+
+
+func getLogger(ctx context.Context) logger.Logger {
+	panic("unimpl")
+}

daemon/job/trigger/manual.go

@@ -0,0 +1,33 @@
+package trigger
+
+import "context"
+
+type Manual struct {
+	id     string
+	signal chan<- struct{}
+}
+
+var _ Trigger = &Manual{}
+
+func NewManual(id string) *Manual {
+	return &Manual{
+		id:     id,
+		signal: nil,
+	}
+}
+
+func (t *Manual) ID() string {
+	return t.id
+}
+
+func (t *Manual) run(ctx context.Context, signal chan<- struct{}) {
+	if t.signal != nil {
+		panic("run must only be called once")
+	}
+	t.signal = signal
+}
+
+// Panics if called before the trigger has been spanwed as part of a `Triggers`.
+func (t *Manual) Fire() {
+	t.signal <- struct{}{}
+}

daemon/job/trigger/periodic.go

@@ -0,0 +1,33 @@
+package trigger
+
+import (
+	"context"
+	"time"
+)
+
+type Periodic struct {
+	interval time.Duration
+}
+
+var _ Trigger = &Periodic{}
+
+func NewPeriodic(interval time.Duration) *Periodic {
+	return &Periodic{
+		interval: interval,
+	}
+}
+
+func (p *Periodic) ID() string { return "periodic" }
+
+func (p *Periodic) run(ctx context.Context, signal chan<- struct{}) {
+	t := time.NewTicker(p.interval)
+	defer t.Stop()
+	for {
+		select {
+		case <-t.C:
+			signal <- struct{}{}
+		case <-ctx.Done():
+			return
+		}
+	}
+}

daemon/job/trigger/trigger.go

@@ -0,0 +1,91 @@
+package trigger
+
+import (
+	"context"
+	"github.com/zrepl/zrepl/daemon/logging/trace"
+)
+
+type Triggers struct {
+	spawned  bool
+	triggers []Trigger
+}
+
+type Trigger interface {
+	ID() string
+	run(context.Context, chan<- struct{})
+}
+
+func Empty() *Triggers {
+	return &Triggers{
+		spawned:  false,
+		triggers: nil,
+	}
+}
+
+func (t *Triggers) Spawn(ctx context.Context, additionalTriggers []Trigger) (chan Trigger, trace.DoneFunc) {
+	if t.spawned {
+		panic("must only spawn once")
+	}
+	t.spawned = true
+	t.triggers = append(t.triggers, additionalTriggers...)
+	sink := make(chan Trigger)
+	endTask := t.spawn(ctx, sink)
+	return sink, endTask
+}
+
+type triggering struct {
+	trigger Trigger
+	handled chan struct{}
+}
+
+func (t *Triggers) spawn(ctx context.Context, sink chan Trigger) trace.DoneFunc {
+	ctx, endTask := trace.WithTask(ctx, "triggers")
+	ctx, add, wait := trace.WithTaskGroup(ctx, "trigger-tasks")
+	triggered := make(chan triggering, len(t.triggers))
+	for _, t := range t.triggers {
+		t := t
+		signal := make(chan struct{})
+		go add(func(ctx context.Context) {
+			t.run(ctx, signal)
+		})
+		go func() {
+			for {
+				select {
+				case <-ctx.Done():
+					return
+				case <-signal:
+					handled := make(chan struct{})
+					select {
+					case triggered <- triggering{trigger: t, handled: handled}:
+					default:
+						panic("this funtion ensures that there's always room in the channel")
+					}
+					select {
+					case <-handled:
+					case <-ctx.Done():
+						return
+					}
+				}
+			}
+		}()
+	}
+	go func() {
+		defer wait()
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case triggering := <-triggered:
+				select {
+				case sink <- triggering.trigger:
+				default:
+					getLogger(ctx).
+						WithField("trigger_id", triggering.trigger.ID()).
+						Warn("dropping triggering because job is busy")
+				}
+				close(triggering.handled)
+			}
+		}
+	}()
+	return endTask
+}

daemon/job/wakeup/wakeup.go

@@ -3,6 +3,8 @@ package wakeup
 import (
 	"context"
 	"errors"
+
+	"github.com/zrepl/zrepl/daemon/job/trigger"
 )
 
 type contextKey int
@@ -17,6 +19,10 @@ func Wait(ctx context.Context) <-chan struct{} {
 	return wc
 }
 
+func Trigger(ctx context.Context) trigger.Trigger {
+	panic("unimpl")
+}
+
 type Func func() error
 
 var AlreadyWokenUp = errors.New("already woken up")

daemon/logging/build_logging.go

@@ -63,6 +63,7 @@ type Subsystem string
 const (
 	SubsysMeta         Subsystem = "meta"
 	SubsysJob          Subsystem = "job"
+	SubsysTrigger      Subsystem = "trigger"
 	SubsysReplication  Subsystem = "repl"
 	SubsysEndpoint     Subsystem = "endpoint"
 	SubsysPruning      Subsystem = "pruning"

daemon/logging/trace/trace.go

@@ -1,6 +1,6 @@
 // package trace provides activity tracing via ctx through Tasks and Spans
 //
-// Basic Concepts
+// # Basic Concepts
 //
 // Tracing can be used to identify where a piece of code spends its time.
 //
@@ -10,51 +10,50 @@
 // to tech-savvy users (albeit not developers).
 //
 // This package provides the concept of Tasks and Spans to express what activity is happening within an application:
-//
-//  - Neither task nor span is really tangible but instead contained within the context.Context tree
-//  - Tasks represent concurrent activity (i.e. goroutines).
-//  - Spans represent a semantic stack trace within a task.
-//
+// - Neither task nor span is really tangible but instead contained within the context.Context tree
+// - Tasks represent concurrent activity (i.e. goroutines).
+// - Spans represent a semantic stack trace within a task.
 // As a consequence, whenever a context is propagated across goroutine boundary, you need to create a child task:
 //
-//   go func(ctx context.Context) {
-//     ctx, endTask = WithTask(ctx, "what-happens-inside-the-child-task")
-//     defer endTask()
-//     // ...
-//   }(ctx)
+//	go func(ctx context.Context) {
+//	  ctx, endTask = WithTask(ctx, "what-happens-inside-the-child-task")
+//	  defer endTask()
+//	  // ...
+//	}(ctx)
 //
 // Within the task, you can open up a hierarchy of spans.
 // In contrast to tasks, which have can multiple concurrently running child tasks,
 // spans must nest and not cross the goroutine boundary.
 //
-//  ctx, endSpan = WithSpan(ctx, "copy-dir")
-//  defer endSpan()
-//  for _, f := range dir.Files() {
-//    func() {
-//      ctx, endSpan := WithSpan(ctx, fmt.Sprintf("copy-file %q", f))
-//      defer endspan()
-//      b, _ := ioutil.ReadFile(f)
-//      _ = ioutil.WriteFile(f + ".copy", b, 0600)
-//    }()
-//  }
+//	ctx, endSpan = WithSpan(ctx, "copy-dir")
+//	defer endSpan()
+//	for _, f := range dir.Files() {
+//	  func() {
+//	    ctx, endSpan := WithSpan(ctx, fmt.Sprintf("copy-file %q", f))
+//	    defer endspan()
+//	    b, _ := ioutil.ReadFile(f)
+//	    _ = ioutil.WriteFile(f + ".copy", b, 0600)
+//	  }()
+//	}
 //
 // In combination:
-//  ctx, endTask = WithTask(ctx, "copy-dirs")
-//  defer endTask()
-//  for i := range dirs {
-//    go func(dir string) {
-//      ctx, endTask := WithTask(ctx, "copy-dir")
-//      defer endTask()
-//      for _, f := range filesIn(dir) {
-//        func() {
-//          ctx, endSpan := WithSpan(ctx, fmt.Sprintf("copy-file %q", f))
-//          defer endspan()
-//          b, _ := ioutil.ReadFile(f)
-//          _ = ioutil.WriteFile(f + ".copy", b, 0600)
-//        }()
-//      }
-//    }()
-//  }
+//
+//	ctx, endTask = WithTask(ctx, "copy-dirs")
+//	defer endTask()
+//	for i := range dirs {
+//	  go func(dir string) {
+//	    ctx, endTask := WithTask(ctx, "copy-dir")
+//	    defer endTask()
+//	    for _, f := range filesIn(dir) {
+//	      func() {
+//	        ctx, endSpan := WithSpan(ctx, fmt.Sprintf("copy-file %q", f))
+//	        defer endspan()
+//	        b, _ := ioutil.ReadFile(f)
+//	        _ = ioutil.WriteFile(f + ".copy", b, 0600)
+//	      }()
+//	    }
+//	  }()
+//	}
 //
 // Note that a span ends at the time you call endSpan - not before and not after that.
 // If you violate the stack-like nesting of spans by forgetting an endSpan() invocation,
@@ -65,8 +64,7 @@
 //
 // Recovering from endSpan() or endTask() panics will corrupt the trace stack and lead to corrupt tracefile output.
 //
-//
-// Best Practices For Naming Tasks And Spans
+// # Best Practices For Naming Tasks And Spans
 //
 // Tasks should always have string constants as names, and must not contain the `#` character. WHy?
 // First, the visualization by chrome://tracing draws a horizontal bar for each task in the trace.
@@ -74,8 +72,7 @@
 // Note that the `#NUM` suffix will be reused if a task has ended, in order to avoid an
 // infinite number of horizontal bars in the visualization.
 //
-//
-// Chrome-compatible Tracefile Support
+// # Chrome-compatible Tracefile Support
 //
 // The activity trace generated by usage of WithTask and WithSpan can be rendered to a JSON output file
 // that can be loaded into chrome://tracing .
@@ -246,7 +243,7 @@ func WithTask(ctx context.Context, taskName string) (context.Context, DoneFunc)
 					// the debugString can be quite long and panic won't print it completely
 					fmt.Fprintf(os.Stderr, "going to panic due to activeChildTasks:\n%s\n", this.debugString())
 				}
-				panic(errors.WithMessagef(ErrTaskStillHasActiveChildTasks, "end task: %v active child tasks\n", this.activeChildTasks))
+				panic(errors.WithMessagef(ErrTaskStillHasActiveChildTasks, "end task: %v active child tasks (run daemon with env var %s=1 for more details)\n", this.activeChildTasks, debugEnabledEnvVar))
 			}
 
 			// support idempotent task ends

daemon/logging/trace/trace_convenience.go

@@ -11,8 +11,6 @@ import (
 // use like this:
 //
 //	defer WithSpanFromStackUpdateCtx(&existingCtx)()
-//
-//
 func WithSpanFromStackUpdateCtx(ctx *context.Context) DoneFunc {
 	childSpanCtx, end := WithSpan(*ctx, getMyCallerOrPanic())
 	*ctx = childSpanCtx

daemon/logging/trace/trace_debug.go

@@ -7,7 +7,9 @@ import (
 	"github.com/zrepl/zrepl/util/envconst"
 )
 
-var debugEnabled = envconst.Bool("ZREPL_TRACE_DEBUG_ENABLED", false)
+const debugEnabledEnvVar = "ZREPL_TRACE_DEBUG_ENABLED"
+
+var debugEnabled = envconst.Bool(debugEnabledEnvVar, false)
 
 func debug(format string, args ...interface{}) {
 	if !debugEnabled {

daemon/pruner/pruner.go

@@ -19,12 +19,20 @@ import (
 	"github.com/zrepl/zrepl/util/envconst"
 )
 
+// The sender in the replication setup.
+// The pruner uses the Sender to determine which of the Target's filesystems need to be pruned.
+// Also, it asks the Sender about the replication cursor of each filesystem
+// to enable the 'not_replicated' pruning rule.
+//
 // Try to keep it compatible with github.com/zrepl/zrepl/endpoint.Endpoint
-type History interface {
+type Sender interface {
 	ReplicationCursor(ctx context.Context, req *pdu.ReplicationCursorReq) (*pdu.ReplicationCursorRes, error)
 	ListFilesystems(ctx context.Context, req *pdu.ListFilesystemReq) (*pdu.ListFilesystemRes, error)
 }
 
+// The pruning target, i.e., on which snapshots are destroyed.
+// This can be a replication sender or receiver.
+//
 // Try to keep it compatible with github.com/zrepl/zrepl/endpoint.Endpoint
 type Target interface {
 	ListFilesystems(ctx context.Context, req *pdu.ListFilesystemReq) (*pdu.ListFilesystemRes, error)
@@ -48,7 +56,7 @@ func GetLogger(ctx context.Context) Logger {
 type args struct {
 	ctx                            context.Context
 	target                         Target
-	receiver                       History
+	sender                         Sender
 	rules                          []pruning.KeepRule
 	retryWait                      time.Duration
 	considerSnapAtCursorReplicated bool
@@ -132,12 +140,12 @@ func NewPrunerFactory(in config.PruningSenderReceiver, promPruneSecs *prometheus
 	return f, nil
 }
 
-func (f *PrunerFactory) BuildSenderPruner(ctx context.Context, target Target, receiver History) *Pruner {
+func (f *PrunerFactory) BuildSenderPruner(ctx context.Context, target Target, sender Sender) *Pruner {
 	p := &Pruner{
 		args: args{
 			context.WithValue(ctx, contextKeyPruneSide, "sender"),
 			target,
-			receiver,
+			sender,
 			f.senderRules,
 			f.retryWait,
 			f.considerSnapAtCursorReplicated,
@@ -148,12 +156,12 @@ func (f *PrunerFactory) BuildSenderPruner(ctx context.Context, target Target, re
 	return p
 }
 
-func (f *PrunerFactory) BuildReceiverPruner(ctx context.Context, target Target, receiver History) *Pruner {
+func (f *PrunerFactory) BuildReceiverPruner(ctx context.Context, target Target, sender Sender) *Pruner {
 	p := &Pruner{
 		args: args{
 			context.WithValue(ctx, contextKeyPruneSide, "receiver"),
 			target,
-			receiver,
+			sender,
 			f.receiverRules,
 			f.retryWait,
 			false, // senseless here anyways
@@ -164,12 +172,12 @@ func (f *PrunerFactory) BuildReceiverPruner(ctx context.Context, target Target,
 	return p
 }
 
-func (f *LocalPrunerFactory) BuildLocalPruner(ctx context.Context, target Target, receiver History) *Pruner {
+func (f *LocalPrunerFactory) BuildLocalPruner(ctx context.Context, target Target, history Sender) *Pruner {
 	p := &Pruner{
 		args: args{
 			context.WithValue(ctx, contextKeyPruneSide, "local"),
 			target,
-			receiver,
+			history,
 			f.keepRules,
 			f.retryWait,
 			false, // considerSnapAtCursorReplicated is not relevant for local pruning
@@ -191,6 +199,16 @@ const (
 	Done
 )
 
+// Returns true in case the State is a terminal state(PlanErr, ExecErr, Done)
+func (s State) IsTerminal() bool {
+	switch s {
+	case PlanErr, ExecErr, Done:
+		return true
+	default:
+		return false
+	}
+}
+
 type updater func(func(*Pruner))
 
 func (p *Pruner) Prune() {
@@ -343,9 +361,9 @@ func (s snapshot) Date() time.Time { return s.date }
 
 func doOneAttempt(a *args, u updater) {
 
-	ctx, target, receiver := a.ctx, a.target, a.receiver
+	ctx, target, sender := a.ctx, a.target, a.sender
 
-	sfssres, err := receiver.ListFilesystems(ctx, &pdu.ListFilesystemReq{})
+	sfssres, err := sender.ListFilesystems(ctx, &pdu.ListFilesystemReq{})
 	if err != nil {
 		u(func(p *Pruner) {
 			p.state = PlanErr
@@ -410,7 +428,7 @@ tfss_loop:
 		rcReq := &pdu.ReplicationCursorReq{
 			Filesystem: tfs.Path,
 		}
-		rc, err := receiver.ReplicationCursor(ctx, rcReq)
+		rc, err := sender.ReplicationCursor(ctx, rcReq)
 		if err != nil {
 			pfsPlanErrAndLog(err, "cannot get replication cursor bookmark")
 			continue tfss_loop
@@ -456,7 +474,7 @@ tfss_loop:
 			})
 		}
 		if preCursor {
-			pfsPlanErrAndLog(fmt.Errorf("replication cursor not found in prune target filesystem versions"), "")
+			pfsPlanErrAndLog(fmt.Errorf("prune target has no snapshot that corresponds to sender replication cursor bookmark"), "")
 			continue tfss_loop
 		}
 

daemon/snapper/cron.go

@@ -0,0 +1,147 @@
+package snapper
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/pkg/errors"
+
+	"github.com/zrepl/zrepl/config"
+	"github.com/zrepl/zrepl/daemon/hooks"
+	"github.com/zrepl/zrepl/daemon/job/trigger"
+	"github.com/zrepl/zrepl/util/suspendresumesafetimer"
+	"github.com/zrepl/zrepl/zfs"
+)
+
+func cronFromConfig(fsf zfs.DatasetFilter, in config.SnapshottingCron) (*Cron, error) {
+
+	hooksList, err := hooks.ListFromConfig(&in.Hooks)
+	if err != nil {
+		return nil, errors.Wrap(err, "hook config error")
+	}
+	planArgs := planArgs{
+		prefix:          in.Prefix,
+		timestampFormat: in.TimestampFormat,
+		hooks:           hooksList,
+	}
+	return &Cron{config: in, fsf: fsf, planArgs: planArgs}, nil
+}
+
+type Cron struct {
+	config   config.SnapshottingCron
+	fsf      zfs.DatasetFilter
+	planArgs planArgs
+
+	mtx sync.RWMutex
+
+	running                 bool
+	wakeupTime              time.Time // zero value means uninit
+	lastError               error
+	lastPlan                *plan
+	wakeupWhileRunningCount int
+}
+
+func (s *Cron) Run(ctx context.Context, snapshotsTaken *trigger.Manual) {
+
+	for {
+		now := time.Now()
+		s.mtx.Lock()
+		s.wakeupTime = s.config.Cron.Schedule.Next(now)
+		s.mtx.Unlock()
+
+		ctxDone := suspendresumesafetimer.SleepUntil(ctx, s.wakeupTime)
+		if ctxDone != nil {
+			return
+		}
+
+		getLogger(ctx).Debug("cron timer fired")
+		s.mtx.Lock()
+		if s.running {
+			getLogger(ctx).Warn("snapshotting triggered according to cron rules but previous snapshotting is not done; not taking a snapshot this time")
+			s.wakeupWhileRunningCount++
+			s.mtx.Unlock()
+			continue
+		}
+		s.lastError = nil
+		s.lastPlan = nil
+		s.wakeupWhileRunningCount = 0
+		s.running = true
+		s.mtx.Unlock()
+		go func() {
+			err := s.do(ctx)
+			s.mtx.Lock()
+			s.lastError = err
+			s.running = false
+			s.mtx.Unlock()
+
+			snapshotsTaken.Fire()
+		}()
+	}
+
+}
+
+func (s *Cron) do(ctx context.Context) error {
+	fss, err := zfs.ZFSListMapping(ctx, s.fsf)
+	if err != nil {
+		return errors.Wrap(err, "cannot list filesystems")
+	}
+	p := makePlan(s.planArgs, fss)
+
+	s.mtx.Lock()
+	s.lastPlan = p
+	s.lastError = nil
+	s.mtx.Unlock()
+
+	ok := p.execute(ctx, false)
+	if !ok {
+		return errors.New("one or more snapshots could not be created, check logs for details")
+	} else {
+		return nil
+	}
+}
+
+type CronState string
+
+const (
+	CronStateRunning CronState = "running"
+	CronStateWaiting CronState = "waiting"
+)
+
+type CronReport struct {
+	State      CronState
+	WakeupTime time.Time
+	Errors     []string
+	Progress   []*ReportFilesystem
+}
+
+func (s *Cron) Report() Report {
+
+	s.mtx.Lock()
+	defer s.mtx.Unlock()
+
+	r := CronReport{}
+
+	r.WakeupTime = s.wakeupTime
+
+	if s.running {
+		r.State = CronStateRunning
+	} else {
+		r.State = CronStateWaiting
+	}
+
+	if s.lastError != nil {
+		r.Errors = append(r.Errors, s.lastError.Error())
+	}
+	if s.wakeupWhileRunningCount > 0 {
+		r.Errors = append(r.Errors, fmt.Sprintf("cron frequency is too high; snapshots were not taken %d times", s.wakeupWhileRunningCount))
+	}
+
+	r.Progress = nil
+	if s.lastPlan != nil {
+		r.Progress = s.lastPlan.report()
+	}
+
+	return Report{Type: TypeCron, Cron: &r}
+}

daemon/snapper/cron_test.go

@@ -0,0 +1,68 @@
+package snapper
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"github.com/zrepl/yaml-config"
+
+	"github.com/zrepl/zrepl/config"
+)
+
+func TestCronLibraryWorks(t *testing.T) {
+
+	type testCase struct {
+		spec   string
+		in     time.Time
+		expect time.Time
+	}
+	dhm := func(day, hour, minutes int) time.Time {
+		return time.Date(2022, 7, day, hour, minutes, 0, 0, time.UTC)
+	}
+	hm := func(hour, minutes int) time.Time {
+		return dhm(23, hour, minutes)
+	}
+
+	tcs := []testCase{
+		{"0-10 * * * *", dhm(17, 1, 10), dhm(17, 2, 0)},
+		{"0-10 * * * *", dhm(17, 23, 10), dhm(18, 0, 0)},
+		{"0-10 * * * *", hm(1, 9), hm(1, 10)},
+		{"0-10 * * * *", hm(1, 9), hm(1, 10)},
+
+		{"1,3,5 * * * *", hm(1, 1), hm(1, 3)},
+		{"1,3,5 * * * *", hm(1, 2), hm(1, 3)},
+		{"1,3,5 * * * *", hm(1, 3), hm(1, 5)},
+		{"1,3,5 * * * *", hm(1, 5), hm(2, 1)},
+
+		{"* 0-5,8,12 * * *", hm(0, 0), hm(0, 1)},
+		{"* 0-5,8,12 * * *", hm(4, 59), hm(5, 0)},
+		{"* 0-5,8,12 * * *", hm(5, 0), hm(5, 1)},
+		{"* 0-5,8,12 * * *", hm(5, 59), hm(8, 0)},
+		{"* 0-5,8,12 * * *", hm(8, 59), hm(12, 0)},
+
+		// https://github.com/zrepl/zrepl/pull/614#issuecomment-1188358989
+		{"53 17,18,19 * * *", dhm(23, 17, 52), dhm(23, 17, 53)},
+		{"53 17,18,19 * * *", dhm(23, 17, 53), dhm(23, 18, 53)},
+		{"53 17,18,19 * * *", dhm(23, 18, 53), dhm(23, 19, 53)},
+		{"53 17,18,19 * * *", dhm(23, 19, 53), dhm(24 /* ! */, 17, 53)},
+	}
+
+	for i, tc := range tcs {
+		t.Run(fmt.Sprintf("%d", i), func(t *testing.T) {
+			var s struct {
+				Cron config.CronSpec `yaml:"cron"`
+			}
+			inp := fmt.Sprintf("cron: %q", tc.spec)
+			fmt.Println("spec is ", inp)
+			err := yaml.UnmarshalStrict([]byte(inp), &s)
+			require.NoError(t, err)
+
+			actual := s.Cron.Schedule.Next(tc.in)
+			assert.Equal(t, tc.expect, actual)
+		})
+	}
+
+}

daemon/snapper/impl.go

@@ -0,0 +1,268 @@
+package snapper
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/zrepl/zrepl/daemon/hooks"
+	"github.com/zrepl/zrepl/daemon/logging"
+	"github.com/zrepl/zrepl/util/chainlock"
+	"github.com/zrepl/zrepl/zfs"
+)
+
+type planArgs struct {
+	prefix          string
+	timestampFormat string
+	hooks           *hooks.List
+}
+
+type plan struct {
+	mtx   chainlock.L
+	args  planArgs
+	snaps map[*zfs.DatasetPath]*snapProgress
+}
+
+func makePlan(args planArgs, fss []*zfs.DatasetPath) *plan {
+	snaps := make(map[*zfs.DatasetPath]*snapProgress, len(fss))
+	for _, fs := range fss {
+		snaps[fs] = &snapProgress{state: SnapPending}
+	}
+	return &plan{snaps: snaps, args: args}
+}
+
+//go:generate stringer -type=SnapState
+type SnapState uint
+
+const (
+	SnapPending SnapState = 1 << iota
+	SnapStarted
+	SnapDone
+	SnapError
+)
+
+// All fields protected by Snapper.mtx
+type snapProgress struct {
+	state SnapState
+
+	// SnapStarted, SnapDone, SnapError
+	name     string
+	startAt  time.Time
+	hookPlan *hooks.Plan
+
+	// SnapDone
+	doneAt time.Time
+
+	// SnapErr TODO disambiguate state
+	runResults hooks.PlanReport
+}
+
+func (plan *plan) formatNow(format string) string {
+	now := time.Now().UTC()
+	switch strings.ToLower(format) {
+	case "dense":
+		format = "20060102_150405_000"
+	case "human":
+		format = "2006-01-02_15:04:05"
+	case "iso-8601":
+		format = "2006-01-02T15:04:05.000Z"
+	case "unix-seconds":
+		return strconv.FormatInt(now.Unix(), 10)
+	}
+	return now.Format(format)
+}
+
+func (plan *plan) execute(ctx context.Context, dryRun bool) (ok bool) {
+
+	hookMatchCount := make(map[hooks.Hook]int, len(*plan.args.hooks))
+	for _, h := range *plan.args.hooks {
+		hookMatchCount[h] = 0
+	}
+
+	anyFsHadErr := false
+	// TODO channel programs -> allow a little jitter?
+	for fs, progress := range plan.snaps {
+		suffix := plan.formatNow(plan.args.timestampFormat)
+		snapname := fmt.Sprintf("%s%s", plan.args.prefix, suffix)
+
+		ctx := logging.WithInjectedField(ctx, "fs", fs.ToString())
+		ctx = logging.WithInjectedField(ctx, "snap", snapname)
+
+		hookEnvExtra := hooks.Env{
+			hooks.EnvFS:       fs.ToString(),
+			hooks.EnvSnapshot: snapname,
+		}
+
+		jobCallback := hooks.NewCallbackHookForFilesystem("snapshot", fs, func(ctx context.Context) (err error) {
+			l := getLogger(ctx)
+			l.Debug("create snapshot")
+			err = zfs.ZFSSnapshot(ctx, fs, snapname, false) // TODO propagate context to ZFSSnapshot
+			if err != nil {
+				l.WithError(err).Error("cannot create snapshot")
+			}
+			return
+		})
+
+		fsHadErr := false
+		var hookPlanReport hooks.PlanReport
+		var hookPlan *hooks.Plan
+		{
+			filteredHooks, err := plan.args.hooks.CopyFilteredForFilesystem(fs)
+			if err != nil {
+				getLogger(ctx).WithError(err).Error("unexpected filter error")
+				fsHadErr = true
+				goto updateFSState
+			}
+			// account for running hooks
+			for _, h := range filteredHooks {
+				hookMatchCount[h] = hookMatchCount[h] + 1
+			}
+
+			var planErr error
+			hookPlan, planErr = hooks.NewPlan(&filteredHooks, hooks.PhaseSnapshot, jobCallback, hookEnvExtra)
+			if planErr != nil {
+				fsHadErr = true
+				getLogger(ctx).WithError(planErr).Error("cannot create job hook plan")
+				goto updateFSState
+			}
+		}
+
+		plan.mtx.HoldWhile(func() {
+			progress.name = snapname
+			progress.startAt = time.Now()
+			progress.hookPlan = hookPlan
+			progress.state = SnapStarted
+		})
+
+		{
+			getLogger(ctx).WithField("report", hookPlan.Report().String()).Debug("begin run job plan")
+			hookPlan.Run(ctx, dryRun)
+			hookPlanReport = hookPlan.Report()
+			fsHadErr = hookPlanReport.HadError() // not just fatal errors
+			if fsHadErr {
+				getLogger(ctx).WithField("report", hookPlanReport.String()).Error("end run job plan with error")
+			} else {
+				getLogger(ctx).WithField("report", hookPlanReport.String()).Info("end run job plan successful")
+			}
+		}
+
+	updateFSState:
+		anyFsHadErr = anyFsHadErr || fsHadErr
+		plan.mtx.HoldWhile(func() {
+			progress.doneAt = time.Now()
+			progress.state = SnapDone
+			if fsHadErr {
+				progress.state = SnapError
+			}
+			progress.runResults = hookPlanReport
+		})
+	}
+
+	for h, mc := range hookMatchCount {
+		if mc == 0 {
+			hookIdx := -1
+			for idx, ah := range *plan.args.hooks {
+				if ah == h {
+					hookIdx = idx
+					break
+				}
+			}
+			getLogger(ctx).WithField("hook", h.String()).WithField("hook_number", hookIdx+1).Warn("hook did not match any snapshotted filesystems")
+		}
+	}
+
+	return !anyFsHadErr
+}
+
+type ReportFilesystem struct {
+	Path  string
+	State SnapState
+
+	// Valid in SnapStarted and later
+	SnapName      string
+	StartAt       time.Time
+	Hooks         string
+	HooksHadError bool
+
+	// Valid in SnapDone | SnapError
+	DoneAt time.Time
+}
+
+func (plan *plan) report() []*ReportFilesystem {
+	plan.mtx.Lock()
+	defer plan.mtx.Unlock()
+
+	pReps := make([]*ReportFilesystem, 0, len(plan.snaps))
+	for fs, p := range plan.snaps {
+		var hooksStr string
+		var hooksHadError bool
+		if p.hookPlan != nil {
+			hooksStr, hooksHadError = p.report()
+		}
+		pReps = append(pReps, &ReportFilesystem{
+			Path:          fs.ToString(),
+			State:         p.state,
+			SnapName:      p.name,
+			StartAt:       p.startAt,
+			DoneAt:        p.doneAt,
+			Hooks:         hooksStr,
+			HooksHadError: hooksHadError,
+		})
+	}
+
+	sort.Slice(pReps, func(i, j int) bool {
+		return strings.Compare(pReps[i].Path, pReps[j].Path) == -1
+	})
+
+	return pReps
+}
+
+func (p *snapProgress) report() (hooksStr string, hooksHadError bool) {
+	hr := p.hookPlan.Report()
+	// FIXME: technically this belongs into client
+	// but we can't serialize hooks.Step ATM
+	rightPad := func(str string, length int, pad string) string {
+		if len(str) > length {
+			return str[:length]
+		}
+		return str + strings.Repeat(pad, length-len(str))
+	}
+	hooksHadError = hr.HadError()
+	rows := make([][]string, len(hr))
+	const numCols = 4
+	lens := make([]int, numCols)
+	for i, e := range hr {
+		rows[i] = make([]string, numCols)
+		rows[i][0] = fmt.Sprintf("%d", i+1)
+		rows[i][1] = e.Status.String()
+		runTime := "..."
+		if e.Status != hooks.StepPending {
+			runTime = e.End.Sub(e.Begin).Round(time.Millisecond).String()
+		}
+		rows[i][2] = runTime
+		rows[i][3] = ""
+		if e.Report != nil {
+			rows[i][3] = e.Report.String()
+		}
+		for j, col := range lens {
+			if len(rows[i][j]) > col {
+				lens[j] = len(rows[i][j])
+			}
+		}
+	}
+	rowsFlat := make([]string, len(hr))
+	for i, r := range rows {
+		colsPadded := make([]string, len(r))
+		for j, c := range r[:len(r)-1] {
+			colsPadded[j] = rightPad(c, lens[j], " ")
+		}
+		colsPadded[len(r)-1] = r[len(r)-1]
+		rowsFlat[i] = strings.Join(colsPadded, " ")
+	}
+	hooksStr = strings.Join(rowsFlat, "\n")
+
+	return hooksStr, hooksHadError
+}

daemon/snapper/manual.go

@@ -0,0 +1,17 @@
+package snapper
+
+import (
+	"context"
+
+	"github.com/zrepl/zrepl/daemon/job/trigger"
+)
+
+type manual struct{}
+
+func (s *manual) Run(ctx context.Context, snapshotsTaken *trigger.Manual) {
+	// nothing to do
+}
+
+func (s *manual) Report() Report {
+	return Report{Type: TypeManual, Manual: &struct{}{}}
+}

daemon/snapper/periodic.go

@@ -0,0 +1,389 @@
+package snapper
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/pkg/errors"
+
+	"github.com/zrepl/zrepl/daemon/job/trigger"
+	"github.com/zrepl/zrepl/daemon/logging/trace"
+
+	"github.com/zrepl/zrepl/config"
+	"github.com/zrepl/zrepl/daemon/hooks"
+	"github.com/zrepl/zrepl/daemon/logging"
+	"github.com/zrepl/zrepl/util/envconst"
+	"github.com/zrepl/zrepl/util/suspendresumesafetimer"
+	"github.com/zrepl/zrepl/zfs"
+)
+
+func periodicFromConfig(g *config.Global, fsf zfs.DatasetFilter, in *config.SnapshottingPeriodic) (*Periodic, error) {
+	if in.Prefix == "" {
+		return nil, errors.New("prefix must not be empty")
+	}
+	if in.Interval.Duration() <= 0 {
+		return nil, errors.New("interval must be positive")
+	}
+
+	hookList, err := hooks.ListFromConfig(&in.Hooks)
+	if err != nil {
+		return nil, errors.Wrap(err, "hook config error")
+	}
+
+	args := periodicArgs{
+		interval: in.Interval.Duration(),
+		fsf:      fsf,
+		planArgs: planArgs{
+			prefix:          in.Prefix,
+			timestampFormat: in.TimestampFormat,
+			hooks:           hookList,
+		},
+		// ctx and log is set in Run()
+	}
+
+	return &Periodic{state: SyncUp, args: args}, nil
+}
+
+type periodicArgs struct {
+	ctx            context.Context
+	interval       time.Duration
+	fsf            zfs.DatasetFilter
+	planArgs       planArgs
+	snapshotsTaken *trigger.Manual
+	dryRun         bool
+}
+
+type Periodic struct {
+	args periodicArgs
+
+	mtx   sync.Mutex
+	state State
+
+	// set in state Plan, used in Waiting
+	lastInvocation time.Time
+
+	// valid for state Snapshotting
+	plan *plan
+
+	// valid for state SyncUp and Waiting
+	sleepUntil time.Time
+
+	// valid for state Err
+	err error
+}
+
+//go:generate stringer -type=State
+type State uint
+
+const (
+	SyncUp State = 1 << iota
+	SyncUpErrWait
+	Planning
+	Snapshotting
+	Waiting
+	ErrorWait
+	Stopped
+)
+
+func (s State) sf() state {
+	m := map[State]state{
+		SyncUp:        periodicStateSyncUp,
+		SyncUpErrWait: periodicStateWait,
+		Planning:      periodicStatePlan,
+		Snapshotting:  periodicStateSnapshot,
+		Waiting:       periodicStateWait,
+		ErrorWait:     periodicStateWait,
+		Stopped:       nil,
+	}
+	return m[s]
+}
+
+type updater func(u func(*Periodic)) State
+type state func(a periodicArgs, u updater) state
+
+func (s *Periodic) Run(ctx context.Context, snapshotsTaken *trigger.Manual) {
+	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
+	getLogger(ctx).Debug("start")
+	defer getLogger(ctx).Debug("stop")
+
+	s.args.snapshotsTaken = snapshotsTaken
+	s.args.ctx = ctx
+	s.args.dryRun = false // for future expansion
+
+	u := func(u func(*Periodic)) State {
+		s.mtx.Lock()
+		defer s.mtx.Unlock()
+		if u != nil {
+			u(s)
+		}
+		return s.state
+	}
+
+	var st state = periodicStateSyncUp
+
+	for st != nil {
+		pre := u(nil)
+		st = st(s.args, u)
+		post := u(nil)
+		getLogger(ctx).
+			WithField("transition", fmt.Sprintf("%s=>%s", pre, post)).
+			Debug("state transition")
+
+	}
+
+}
+
+func onErr(err error, u updater) state {
+	return u(func(s *Periodic) {
+		s.err = err
+		preState := s.state
+		switch s.state {
+		case SyncUp:
+			s.state = SyncUpErrWait
+		case Planning:
+			fallthrough
+		case Snapshotting:
+			s.state = ErrorWait
+		}
+		getLogger(s.args.ctx).WithError(err).WithField("pre_state", preState).WithField("post_state", s.state).Error("snapshotting error")
+	}).sf()
+}
+
+func onMainCtxDone(ctx context.Context, u updater) state {
+	return u(func(s *Periodic) {
+		s.err = ctx.Err()
+		s.state = Stopped
+	}).sf()
+}
+
+func periodicStateSyncUp(a periodicArgs, u updater) state {
+	u(func(snapper *Periodic) {
+		snapper.lastInvocation = time.Now()
+	})
+	fss, err := listFSes(a.ctx, a.fsf)
+	if err != nil {
+		return onErr(err, u)
+	}
+	syncPoint, err := findSyncPoint(a.ctx, fss, a.planArgs.prefix, a.interval)
+	if err != nil {
+		return onErr(err, u)
+	}
+	u(func(s *Periodic) {
+		s.sleepUntil = syncPoint
+	})
+	ctxDone := suspendresumesafetimer.SleepUntil(a.ctx, syncPoint)
+	if ctxDone != nil {
+		return onMainCtxDone(a.ctx, u)
+	}
+	return u(func(s *Periodic) {
+		s.state = Planning
+	}).sf()
+}
+
+func periodicStatePlan(a periodicArgs, u updater) state {
+	u(func(snapper *Periodic) {
+		snapper.lastInvocation = time.Now()
+	})
+	fss, err := listFSes(a.ctx, a.fsf)
+	if err != nil {
+		return onErr(err, u)
+	}
+	p := makePlan(a.planArgs, fss)
+	return u(func(s *Periodic) {
+		s.state = Snapshotting
+		s.plan = p
+		s.err = nil
+	}).sf()
+}
+
+func periodicStateSnapshot(a periodicArgs, u updater) state {
+
+	var plan *plan
+	u(func(snapper *Periodic) {
+		plan = snapper.plan
+	})
+
+	ok := plan.execute(a.ctx, false)
+
+	a.snapshotsTaken.Fire()
+
+	return u(func(snapper *Periodic) {
+		if !ok {
+			snapper.state = ErrorWait
+			snapper.err = errors.New("one or more snapshots could not be created, check logs for details")
+		} else {
+			snapper.state = Waiting
+			snapper.err = nil
+		}
+	}).sf()
+}
+
+func periodicStateWait(a periodicArgs, u updater) state {
+	var sleepUntil time.Time
+	u(func(snapper *Periodic) {
+		lastTick := snapper.lastInvocation
+		snapper.sleepUntil = lastTick.Add(a.interval)
+		sleepUntil = snapper.sleepUntil
+		log := getLogger(a.ctx).WithField("sleep_until", sleepUntil).WithField("duration", a.interval)
+		logFunc := log.Debug
+		if snapper.state == ErrorWait || snapper.state == SyncUpErrWait {
+			logFunc = log.Error
+		}
+		logFunc("enter wait-state after error")
+	})
+
+	ctxDone := suspendresumesafetimer.SleepUntil(a.ctx, sleepUntil)
+	if ctxDone != nil {
+		return onMainCtxDone(a.ctx, u)
+	}
+	return u(func(snapper *Periodic) {
+		snapper.state = Planning
+	}).sf()
+}
+
+func listFSes(ctx context.Context, mf zfs.DatasetFilter) (fss []*zfs.DatasetPath, err error) {
+	return zfs.ZFSListMapping(ctx, mf)
+}
+
+var syncUpWarnNoSnapshotUntilSyncupMinDuration = envconst.Duration("ZREPL_SNAPPER_SYNCUP_WARN_MIN_DURATION", 1*time.Second)
+
+// see docs/snapshotting.rst
+func findSyncPoint(ctx context.Context, fss []*zfs.DatasetPath, prefix string, interval time.Duration) (syncPoint time.Time, err error) {
+
+	const (
+		prioHasVersions int = iota
+		prioNoVersions
+	)
+
+	type snapTime struct {
+		ds   *zfs.DatasetPath
+		prio int // lower is higher
+		time time.Time
+	}
+
+	if len(fss) == 0 {
+		return time.Now(), nil
+	}
+
+	snaptimes := make([]snapTime, 0, len(fss))
+	hardErrs := 0
+
+	now := time.Now()
+
+	getLogger(ctx).Debug("examine filesystem state to find sync point")
+	for _, d := range fss {
+		ctx := logging.WithInjectedField(ctx, "fs", d.ToString())
+		syncPoint, err := findSyncPointFSNextOptimalSnapshotTime(ctx, now, interval, prefix, d)
+		if err == findSyncPointFSNoFilesystemVersionsErr {
+			snaptimes = append(snaptimes, snapTime{
+				ds:   d,
+				prio: prioNoVersions,
+				time: now,
+			})
+		} else if err != nil {
+			hardErrs++
+			getLogger(ctx).WithError(err).Error("cannot determine optimal sync point for this filesystem")
+		} else {
+			getLogger(ctx).WithField("syncPoint", syncPoint).Debug("found optimal sync point for this filesystem")
+			snaptimes = append(snaptimes, snapTime{
+				ds:   d,
+				prio: prioHasVersions,
+				time: syncPoint,
+			})
+		}
+	}
+
+	if hardErrs == len(fss) {
+		return time.Time{}, fmt.Errorf("hard errors in determining sync point for every matching filesystem")
+	}
+
+	if len(snaptimes) == 0 {
+		panic("implementation error: loop must either inc hardErrs or add result to snaptimes")
+	}
+
+	// sort ascending by (prio,time)
+	// => those filesystems with versions win over those without any
+	sort.Slice(snaptimes, func(i, j int) bool {
+		if snaptimes[i].prio == snaptimes[j].prio {
+			return snaptimes[i].time.Before(snaptimes[j].time)
+		}
+		return snaptimes[i].prio < snaptimes[j].prio
+	})
+
+	winnerSyncPoint := snaptimes[0].time
+	l := getLogger(ctx).WithField("syncPoint", winnerSyncPoint.String())
+	l.Info("determined sync point")
+	if winnerSyncPoint.Sub(now) > syncUpWarnNoSnapshotUntilSyncupMinDuration {
+		for _, st := range snaptimes {
+			if st.prio == prioNoVersions {
+				l.WithField("fs", st.ds.ToString()).Warn("filesystem will not be snapshotted until sync point")
+			}
+		}
+	}
+
+	return snaptimes[0].time, nil
+
+}
+
+var findSyncPointFSNoFilesystemVersionsErr = fmt.Errorf("no filesystem versions")
+
+func findSyncPointFSNextOptimalSnapshotTime(ctx context.Context, now time.Time, interval time.Duration, prefix string, d *zfs.DatasetPath) (time.Time, error) {
+
+	fsvs, err := zfs.ZFSListFilesystemVersions(ctx, d, zfs.ListFilesystemVersionsOptions{
+		Types:           zfs.Snapshots,
+		ShortnamePrefix: prefix,
+	})
+	if err != nil {
+		return time.Time{}, errors.Wrap(err, "list filesystem versions")
+	}
+	if len(fsvs) <= 0 {
+		return time.Time{}, findSyncPointFSNoFilesystemVersionsErr
+	}
+
+	// Sort versions by creation
+	sort.SliceStable(fsvs, func(i, j int) bool {
+		return fsvs[i].CreateTXG < fsvs[j].CreateTXG
+	})
+
+	latest := fsvs[len(fsvs)-1]
+	getLogger(ctx).WithField("creation", latest.Creation).Debug("found latest snapshot")
+
+	since := now.Sub(latest.Creation)
+	if since < 0 {
+		return time.Time{}, fmt.Errorf("snapshot %q is from the future: creation=%q now=%q", latest.ToAbsPath(d), latest.Creation, now)
+	}
+
+	return latest.Creation.Add(interval), nil
+}
+
+type PeriodicReport struct {
+	State State
+	// valid in state SyncUp and Waiting
+	SleepUntil time.Time
+	// valid in state Err
+	Error string
+	// valid in state Snapshotting
+	Progress []*ReportFilesystem
+}
+
+func (s *Periodic) Report() Report {
+	s.mtx.Lock()
+	defer s.mtx.Unlock()
+
+	var progress []*ReportFilesystem = nil
+	if s.plan != nil {
+		progress = s.plan.report()
+	}
+
+	r := &PeriodicReport{
+		State:      s.state,
+		SleepUntil: s.sleepUntil,
+		Error:      errOrEmptyString(s.err),
+		Progress:   progress,
+	}
+
+	return Report{Type: TypePeriodic, Periodic: r}
+}

daemon/snapper/snapper.go

@@ -3,497 +3,41 @@ package snapper
 import (
 	"context"
 	"fmt"
-	"sort"
-	"sync"
-	"time"
-
-	"github.com/pkg/errors"
-
-	"github.com/zrepl/zrepl/daemon/logging/trace"
 
 	"github.com/zrepl/zrepl/config"
-	"github.com/zrepl/zrepl/daemon/hooks"
-	"github.com/zrepl/zrepl/daemon/logging"
-	"github.com/zrepl/zrepl/logger"
-	"github.com/zrepl/zrepl/util/envconst"
+	"github.com/zrepl/zrepl/daemon/job/trigger"
 	"github.com/zrepl/zrepl/zfs"
 )
 
-//go:generate stringer -type=SnapState
-type SnapState uint
+type Type string
 
 const (
-	SnapPending SnapState = 1 << iota
-	SnapStarted
-	SnapDone
-	SnapError
+	TypePeriodic Type = "periodic"
+	TypeCron     Type = "cron"
+	TypeManual   Type = "manual"
 )
 
-// All fields protected by Snapper.mtx
-type snapProgress struct {
-	state SnapState
-
-	// SnapStarted, SnapDone, SnapError
-	name     string
-	startAt  time.Time
-	hookPlan *hooks.Plan
-
-	// SnapDone
-	doneAt time.Time
-
-	// SnapErr TODO disambiguate state
-	runResults hooks.PlanReport
+type Snapper interface {
+	Run(ctx context.Context, snapshotsTaken *trigger.Manual)
+	Report() Report
 }
 
-type args struct {
-	ctx            context.Context
-	prefix         string
-	interval       time.Duration
-	fsf            zfs.DatasetFilter
-	snapshotsTaken chan<- struct{}
-	hooks          *hooks.List
-	dryRun         bool
+type Report struct {
+	Type     Type
+	Periodic *PeriodicReport
+	Cron     *CronReport
+	Manual   *struct{}
 }
 
-type Snapper struct {
-	args args
-
-	mtx   sync.Mutex
-	state State
-
-	// set in state Plan, used in Waiting
-	lastInvocation time.Time
-
-	// valid for state Snapshotting
-	plan map[*zfs.DatasetPath]*snapProgress
-
-	// valid for state SyncUp and Waiting
-	sleepUntil time.Time
-
-	// valid for state Err
-	err error
-}
-
-//go:generate stringer -type=State
-type State uint
-
-const (
-	SyncUp State = 1 << iota
-	SyncUpErrWait
-	Planning
-	Snapshotting
-	Waiting
-	ErrorWait
-	Stopped
-)
-
-func (s State) sf() state {
-	m := map[State]state{
-		SyncUp:        syncUp,
-		SyncUpErrWait: wait,
-		Planning:      plan,
-		Snapshotting:  snapshot,
-		Waiting:       wait,
-		ErrorWait:     wait,
-		Stopped:       nil,
-	}
-	return m[s]
-}
-
-type updater func(u func(*Snapper)) State
-type state func(a args, u updater) state
-
-type Logger = logger.Logger
-
-func getLogger(ctx context.Context) Logger {
-	return logging.GetLogger(ctx, logging.SubsysSnapshot)
-}
-
-func PeriodicFromConfig(g *config.Global, fsf zfs.DatasetFilter, in *config.SnapshottingPeriodic) (*Snapper, error) {
-	if in.Prefix == "" {
-		return nil, errors.New("prefix must not be empty")
-	}
-	if in.Interval <= 0 {
-		return nil, errors.New("interval must be positive")
-	}
-
-	hookList, err := hooks.ListFromConfig(&in.Hooks)
-	if err != nil {
-		return nil, errors.Wrap(err, "hook config error")
-	}
-
-	args := args{
-		prefix:   in.Prefix,
-		interval: in.Interval,
-		fsf:      fsf,
-		hooks:    hookList,
-		// ctx and log is set in Run()
-	}
-
-	return &Snapper{state: SyncUp, args: args}, nil
-}
-
-func (s *Snapper) Run(ctx context.Context, snapshotsTaken chan<- struct{}) {
-	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
-	getLogger(ctx).Debug("start")
-	defer getLogger(ctx).Debug("stop")
-
-	s.args.snapshotsTaken = snapshotsTaken
-	s.args.ctx = ctx
-	s.args.dryRun = false // for future expansion
-
-	u := func(u func(*Snapper)) State {
-		s.mtx.Lock()
-		defer s.mtx.Unlock()
-		if u != nil {
-			u(s)
-		}
-		return s.state
-	}
-
-	var st state = syncUp
-
-	for st != nil {
-		pre := u(nil)
-		st = st(s.args, u)
-		post := u(nil)
-		getLogger(ctx).
-			WithField("transition", fmt.Sprintf("%s=>%s", pre, post)).
-			Debug("state transition")
-
-	}
-
-}
-
-func onErr(err error, u updater) state {
-	return u(func(s *Snapper) {
-		s.err = err
-		preState := s.state
-		switch s.state {
-		case SyncUp:
-			s.state = SyncUpErrWait
-		case Planning:
-			fallthrough
-		case Snapshotting:
-			s.state = ErrorWait
-		}
-		getLogger(s.args.ctx).WithError(err).WithField("pre_state", preState).WithField("post_state", s.state).Error("snapshotting error")
-	}).sf()
-}
-
-func onMainCtxDone(ctx context.Context, u updater) state {
-	return u(func(s *Snapper) {
-		s.err = ctx.Err()
-		s.state = Stopped
-	}).sf()
-}
-
-func syncUp(a args, u updater) state {
-	u(func(snapper *Snapper) {
-		snapper.lastInvocation = time.Now()
-	})
-	fss, err := listFSes(a.ctx, a.fsf)
-	if err != nil {
-		return onErr(err, u)
-	}
-	syncPoint, err := findSyncPoint(a.ctx, fss, a.prefix, a.interval)
-	if err != nil {
-		return onErr(err, u)
-	}
-	u(func(s *Snapper) {
-		s.sleepUntil = syncPoint
-	})
-	t := time.NewTimer(time.Until(syncPoint))
-	defer t.Stop()
-	select {
-	case <-t.C:
-		return u(func(s *Snapper) {
-			s.state = Planning
-		}).sf()
-	case <-a.ctx.Done():
-		return onMainCtxDone(a.ctx, u)
-	}
-}
-
-func plan(a args, u updater) state {
-	u(func(snapper *Snapper) {
-		snapper.lastInvocation = time.Now()
-	})
-	fss, err := listFSes(a.ctx, a.fsf)
-	if err != nil {
-		return onErr(err, u)
-	}
-
-	plan := make(map[*zfs.DatasetPath]*snapProgress, len(fss))
-	for _, fs := range fss {
-		plan[fs] = &snapProgress{state: SnapPending}
-	}
-	return u(func(s *Snapper) {
-		s.state = Snapshotting
-		s.plan = plan
-		s.err = nil
-	}).sf()
-}
-
-func snapshot(a args, u updater) state {
-
-	var plan map[*zfs.DatasetPath]*snapProgress
-	u(func(snapper *Snapper) {
-		plan = snapper.plan
-	})
-
-	hookMatchCount := make(map[hooks.Hook]int, len(*a.hooks))
-	for _, h := range *a.hooks {
-		hookMatchCount[h] = 0
-	}
-
-	anyFsHadErr := false
-	// TODO channel programs -> allow a little jitter?
-	for fs, progress := range plan {
-		suffix := time.Now().In(time.UTC).Format("20060102_150405_000")
-		snapname := fmt.Sprintf("%s%s", a.prefix, suffix)
-
-		ctx := logging.WithInjectedField(a.ctx, "fs", fs.ToString())
-		ctx = logging.WithInjectedField(ctx, "snap", snapname)
-
-		hookEnvExtra := hooks.Env{
-			hooks.EnvFS:       fs.ToString(),
-			hooks.EnvSnapshot: snapname,
-		}
-
-		jobCallback := hooks.NewCallbackHookForFilesystem("snapshot", fs, func(ctx context.Context) (err error) {
-			l := getLogger(ctx)
-			l.Debug("create snapshot")
-			err = zfs.ZFSSnapshot(ctx, fs, snapname, false) // TODO propagate context to ZFSSnapshot
-			if err != nil {
-				l.WithError(err).Error("cannot create snapshot")
-			}
-			return
-		})
-
-		fsHadErr := false
-		var planReport hooks.PlanReport
-		var plan *hooks.Plan
-		{
-			filteredHooks, err := a.hooks.CopyFilteredForFilesystem(fs)
-			if err != nil {
-				getLogger(ctx).WithError(err).Error("unexpected filter error")
-				fsHadErr = true
-				goto updateFSState
-			}
-			// account for running hooks
-			for _, h := range filteredHooks {
-				hookMatchCount[h] = hookMatchCount[h] + 1
-			}
-
-			var planErr error
-			plan, planErr = hooks.NewPlan(&filteredHooks, hooks.PhaseSnapshot, jobCallback, hookEnvExtra)
-			if planErr != nil {
-				fsHadErr = true
-				getLogger(ctx).WithError(planErr).Error("cannot create job hook plan")
-				goto updateFSState
-			}
-		}
-		u(func(snapper *Snapper) {
-			progress.name = snapname
-			progress.startAt = time.Now()
-			progress.hookPlan = plan
-			progress.state = SnapStarted
-		})
-		{
-			getLogger(ctx).WithField("report", plan.Report().String()).Debug("begin run job plan")
-			plan.Run(ctx, a.dryRun)
-			planReport = plan.Report()
-			fsHadErr = planReport.HadError() // not just fatal errors
-			if fsHadErr {
-				getLogger(ctx).WithField("report", planReport.String()).Error("end run job plan with error")
-			} else {
-				getLogger(ctx).WithField("report", planReport.String()).Info("end run job plan successful")
-			}
-		}
-
-	updateFSState:
-		anyFsHadErr = anyFsHadErr || fsHadErr
-		u(func(snapper *Snapper) {
-			progress.doneAt = time.Now()
-			progress.state = SnapDone
-			if fsHadErr {
-				progress.state = SnapError
-			}
-			progress.runResults = planReport
-		})
-	}
-
-	select {
-	case a.snapshotsTaken <- struct{}{}:
+func FromConfig(g *config.Global, fsf zfs.DatasetFilter, in config.SnapshottingEnum) (Snapper, error) {
+	switch v := in.Ret.(type) {
+	case *config.SnapshottingPeriodic:
+		return periodicFromConfig(g, fsf, v)
+	case *config.SnapshottingCron:
+		return cronFromConfig(fsf, *v)
+	case *config.SnapshottingManual:
+		return &manual{}, nil
 	default:
-		if a.snapshotsTaken != nil {
-			getLogger(a.ctx).Warn("callback channel is full, discarding snapshot update event")
-		}
-	}
-
-	for h, mc := range hookMatchCount {
-		if mc == 0 {
-			hookIdx := -1
-			for idx, ah := range *a.hooks {
-				if ah == h {
-					hookIdx = idx
-					break
-				}
-			}
-			getLogger(a.ctx).WithField("hook", h.String()).WithField("hook_number", hookIdx+1).Warn("hook did not match any snapshotted filesystems")
-		}
-	}
-
-	return u(func(snapper *Snapper) {
-		if anyFsHadErr {
-			snapper.state = ErrorWait
-			snapper.err = errors.New("one or more snapshots could not be created, check logs for details")
-		} else {
-			snapper.state = Waiting
-			snapper.err = nil
-		}
-	}).sf()
-}
-
-func wait(a args, u updater) state {
-	var sleepUntil time.Time
-	u(func(snapper *Snapper) {
-		lastTick := snapper.lastInvocation
-		snapper.sleepUntil = lastTick.Add(a.interval)
-		sleepUntil = snapper.sleepUntil
-		log := getLogger(a.ctx).WithField("sleep_until", sleepUntil).WithField("duration", a.interval)
-		logFunc := log.Debug
-		if snapper.state == ErrorWait || snapper.state == SyncUpErrWait {
-			logFunc = log.Error
-		}
-		logFunc("enter wait-state after error")
-	})
-
-	t := time.NewTimer(time.Until(sleepUntil))
-	defer t.Stop()
-
-	select {
-	case <-t.C:
-		return u(func(snapper *Snapper) {
-			snapper.state = Planning
-		}).sf()
-	case <-a.ctx.Done():
-		return onMainCtxDone(a.ctx, u)
+		return nil, fmt.Errorf("unknown snapshotting type %T", v)
 	}
 }
-
-func listFSes(ctx context.Context, mf zfs.DatasetFilter) (fss []*zfs.DatasetPath, err error) {
-	return zfs.ZFSListMapping(ctx, mf)
-}
-
-var syncUpWarnNoSnapshotUntilSyncupMinDuration = envconst.Duration("ZREPL_SNAPPER_SYNCUP_WARN_MIN_DURATION", 1*time.Second)
-
-// see docs/snapshotting.rst
-func findSyncPoint(ctx context.Context, fss []*zfs.DatasetPath, prefix string, interval time.Duration) (syncPoint time.Time, err error) {
-
-	const (
-		prioHasVersions int = iota
-		prioNoVersions
-	)
-
-	type snapTime struct {
-		ds   *zfs.DatasetPath
-		prio int // lower is higher
-		time time.Time
-	}
-
-	if len(fss) == 0 {
-		return time.Now(), nil
-	}
-
-	snaptimes := make([]snapTime, 0, len(fss))
-	hardErrs := 0
-
-	now := time.Now()
-
-	getLogger(ctx).Debug("examine filesystem state to find sync point")
-	for _, d := range fss {
-		ctx := logging.WithInjectedField(ctx, "fs", d.ToString())
-		syncPoint, err := findSyncPointFSNextOptimalSnapshotTime(ctx, now, interval, prefix, d)
-		if err == findSyncPointFSNoFilesystemVersionsErr {
-			snaptimes = append(snaptimes, snapTime{
-				ds:   d,
-				prio: prioNoVersions,
-				time: now,
-			})
-		} else if err != nil {
-			hardErrs++
-			getLogger(ctx).WithError(err).Error("cannot determine optimal sync point for this filesystem")
-		} else {
-			getLogger(ctx).WithField("syncPoint", syncPoint).Debug("found optimal sync point for this filesystem")
-			snaptimes = append(snaptimes, snapTime{
-				ds:   d,
-				prio: prioHasVersions,
-				time: syncPoint,
-			})
-		}
-	}
-
-	if hardErrs == len(fss) {
-		return time.Time{}, fmt.Errorf("hard errors in determining sync point for every matching filesystem")
-	}
-
-	if len(snaptimes) == 0 {
-		panic("implementation error: loop must either inc hardErrs or add result to snaptimes")
-	}
-
-	// sort ascending by (prio,time)
-	// => those filesystems with versions win over those without any
-	sort.Slice(snaptimes, func(i, j int) bool {
-		if snaptimes[i].prio == snaptimes[j].prio {
-			return snaptimes[i].time.Before(snaptimes[j].time)
-		}
-		return snaptimes[i].prio < snaptimes[j].prio
-	})
-
-	winnerSyncPoint := snaptimes[0].time
-	l := getLogger(ctx).WithField("syncPoint", winnerSyncPoint.String())
-	l.Info("determined sync point")
-	if winnerSyncPoint.Sub(now) > syncUpWarnNoSnapshotUntilSyncupMinDuration {
-		for _, st := range snaptimes {
-			if st.prio == prioNoVersions {
-				l.WithField("fs", st.ds.ToString()).Warn("filesystem will not be snapshotted until sync point")
-			}
-		}
-	}
-
-	return snaptimes[0].time, nil
-
-}
-
-var findSyncPointFSNoFilesystemVersionsErr = fmt.Errorf("no filesystem versions")
-
-func findSyncPointFSNextOptimalSnapshotTime(ctx context.Context, now time.Time, interval time.Duration, prefix string, d *zfs.DatasetPath) (time.Time, error) {
-
-	fsvs, err := zfs.ZFSListFilesystemVersions(ctx, d, zfs.ListFilesystemVersionsOptions{
-		Types:           zfs.Snapshots,
-		ShortnamePrefix: prefix,
-	})
-	if err != nil {
-		return time.Time{}, errors.Wrap(err, "list filesystem versions")
-	}
-	if len(fsvs) <= 0 {
-		return time.Time{}, findSyncPointFSNoFilesystemVersionsErr
-	}
-
-	// Sort versions by creation
-	sort.SliceStable(fsvs, func(i, j int) bool {
-		return fsvs[i].CreateTXG < fsvs[j].CreateTXG
-	})
-
-	latest := fsvs[len(fsvs)-1]
-	getLogger(ctx).WithField("creation", latest.Creation).Debug("found latest snapshot")
-
-	since := now.Sub(latest.Creation)
-	if since < 0 {
-		return time.Time{}, fmt.Errorf("snapshot %q is from the future: creation=%q now=%q", latest.ToAbsPath(d), latest.Creation, now)
-	}
-
-	return latest.Creation.Add(interval), nil
-}

daemon/snapper/snapper_all.go

@@ -1,48 +0,0 @@
-package snapper
-
-import (
-	"context"
-	"fmt"
-
-	"github.com/zrepl/zrepl/config"
-	"github.com/zrepl/zrepl/zfs"
-)
-
-// FIXME: properly abstract snapshotting:
-//   - split up things that trigger snapshotting from the mechanism
-//     - timer-based trigger (periodic)
-//     - call from control socket (manual)
-//     - mixed modes?
-//   - support a `zrepl snapshot JOBNAME` subcommand for config.SnapshottingManual
-type PeriodicOrManual struct {
-	s *Snapper
-}
-
-func (s *PeriodicOrManual) Run(ctx context.Context, wakeUpCommon chan<- struct{}) {
-	if s.s != nil {
-		s.s.Run(ctx, wakeUpCommon)
-	}
-}
-
-// Returns nil if manual
-func (s *PeriodicOrManual) Report() *Report {
-	if s.s != nil {
-		return s.s.Report()
-	}
-	return nil
-}
-
-func FromConfig(g *config.Global, fsf zfs.DatasetFilter, in config.SnapshottingEnum) (*PeriodicOrManual, error) {
-	switch v := in.Ret.(type) {
-	case *config.SnapshottingPeriodic:
-		snapper, err := PeriodicFromConfig(g, fsf, v)
-		if err != nil {
-			return nil, err
-		}
-		return &PeriodicOrManual{snapper}, nil
-	case *config.SnapshottingManual:
-		return &PeriodicOrManual{}, nil
-	default:
-		return nil, fmt.Errorf("unknown snapshotting type %T", v)
-	}
-}

daemon/snapper/snapper_report.go

@@ -1,118 +0,0 @@
-package snapper
-
-import (
-	"fmt"
-	"sort"
-	"strings"
-	"time"
-
-	"github.com/zrepl/zrepl/daemon/hooks"
-)
-
-type Report struct {
-	State State
-	// valid in state SyncUp and Waiting
-	SleepUntil time.Time
-	// valid in state Err
-	Error string
-	// valid in state Snapshotting
-	Progress []*ReportFilesystem
-}
-
-type ReportFilesystem struct {
-	Path  string
-	State SnapState
-
-	// Valid in SnapStarted and later
-	SnapName      string
-	StartAt       time.Time
-	Hooks         string
-	HooksHadError bool
-
-	// Valid in SnapDone | SnapError
-	DoneAt time.Time
-}
-
-func errOrEmptyString(e error) string {
-	if e != nil {
-		return e.Error()
-	}
-	return ""
-}
-
-func (s *Snapper) Report() *Report {
-	s.mtx.Lock()
-	defer s.mtx.Unlock()
-
-	pReps := make([]*ReportFilesystem, 0, len(s.plan))
-	for fs, p := range s.plan {
-		var hooksStr string
-		var hooksHadError bool
-		if p.hookPlan != nil {
-			hr := p.hookPlan.Report()
-			// FIXME: technically this belongs into client
-			// but we can't serialize hooks.Step ATM
-			rightPad := func(str string, length int, pad string) string {
-				if len(str) > length {
-					return str[:length]
-				}
-				return str + strings.Repeat(pad, length-len(str))
-			}
-			hooksHadError = hr.HadError()
-			rows := make([][]string, len(hr))
-			const numCols = 4
-			lens := make([]int, numCols)
-			for i, e := range hr {
-				rows[i] = make([]string, numCols)
-				rows[i][0] = fmt.Sprintf("%d", i+1)
-				rows[i][1] = e.Status.String()
-				runTime := "..."
-				if e.Status != hooks.StepPending {
-					runTime = e.End.Sub(e.Begin).Round(time.Millisecond).String()
-				}
-				rows[i][2] = runTime
-				rows[i][3] = ""
-				if e.Report != nil {
-					rows[i][3] = e.Report.String()
-				}
-				for j, col := range lens {
-					if len(rows[i][j]) > col {
-						lens[j] = len(rows[i][j])
-					}
-				}
-			}
-			rowsFlat := make([]string, len(hr))
-			for i, r := range rows {
-				colsPadded := make([]string, len(r))
-				for j, c := range r[:len(r)-1] {
-					colsPadded[j] = rightPad(c, lens[j], " ")
-				}
-				colsPadded[len(r)-1] = r[len(r)-1]
-				rowsFlat[i] = strings.Join(colsPadded, " ")
-			}
-			hooksStr = strings.Join(rowsFlat, "\n")
-		}
-		pReps = append(pReps, &ReportFilesystem{
-			Path:          fs.ToString(),
-			State:         p.state,
-			SnapName:      p.name,
-			StartAt:       p.startAt,
-			DoneAt:        p.doneAt,
-			Hooks:         hooksStr,
-			HooksHadError: hooksHadError,
-		})
-	}
-
-	sort.Slice(pReps, func(i, j int) bool {
-		return strings.Compare(pReps[i].Path, pReps[j].Path) == -1
-	})
-
-	r := &Report{
-		State:      s.state,
-		SleepUntil: s.sleepUntil,
-		Error:      errOrEmptyString(s.err),
-		Progress:   pReps,
-	}
-
-	return r
-}

daemon/snapper/util.go

@@ -0,0 +1,21 @@
+package snapper
+
+import (
+	"context"
+
+	"github.com/zrepl/zrepl/daemon/logging"
+	"github.com/zrepl/zrepl/logger"
+)
+
+type Logger = logger.Logger
+
+func getLogger(ctx context.Context) Logger {
+	return logging.GetLogger(ctx, logging.SubsysSnapshot)
+}
+
+func errOrEmptyString(e error) string {
+	if e != nil {
+		return e.Error()
+	}
+	return ""
+}

dist/openrc/zrepl

@@ -0,0 +1,23 @@
+#!/sbin/openrc-run
+
+command='/usr/local/bin/zrepl'
+command_args='daemon'
+command_background='true'
+pidfile="/run/${RC_SVCNAME}.pid"
+output_log="/var/log/${RC_SVCNAME}.log"
+error_log="/var/log/${RC_SVCNAME}.log"
+
+zrepl_runtime_dir='/var/run/zrepl'
+
+start() {
+	mkdir -p "$zrepl_runtime_dir/stdinserver"
+	chmod -R 0700 "$zrepl_runtime_dir"
+	default_start
+}
+
+stop() {
+	rm -rf "$zrepl_runtime_dir"
+	default_stop
+}
+
+# vi: noet sw=8 sts=0

dist/systemd/zrepl.service

@@ -9,6 +9,9 @@ ExecStart=/usr/local/bin/zrepl --config /etc/zrepl/zrepl.yml daemon
 RuntimeDirectory=zrepl zrepl/stdinserver
 RuntimeDirectoryMode=0700
 
+# Make Go produce coredumps
+Environment=GOTRACEBACK='crash'
+
 ProtectSystem=strict
 #PrivateDevices=yes # TODO ZFS needs access to /dev/zfs, could we limit this?
 ProtectKernelTunables=yes
@@ -27,7 +30,8 @@ ProtectHome=read-only
 # SystemCallFilter
 #   ~@privileged doesn't work with Ubuntu 18.04 ssh
 SystemCallFilter=~ @mount @cpu-emulation @keyring @module @obsolete @raw-io @debug @clock @resources
-
+# Go1.19 added automatic RLIMIT_NOFILE changes, so, we need to allow that
+SystemCallFilter= setrlimit
 
 [Install]
 WantedBy=multi-user.target

docs/Makefile

@@ -10,11 +10,11 @@ BUILDDIR      = _build
 
 # Put it first so that "make" without argument is like "make help".
 help:
-	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" -c sphinxconf $(SPHINXOPTS) $(O)
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
 .PHONY: help Makefile
 
 # Catch-all target: route all unknown targets to Sphinx using the new
 # "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
 %: Makefile
-	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" -c sphinxconf $(SPHINXOPTS) $(O)
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

docs/_static/banner.css

@@ -0,0 +1,43 @@
+/* https://github.com/sphinx-contrib/sphinxcontrib-versioning/blob/0b56210959c6b21bbb730072e81876491b4e1371/sphinxcontrib/versioning/_static/banner.css */
+
+.scv-banner {
+    padding: 3px;
+    border-radius: 2px;
+    font-size: 80%;
+    text-align: center;
+    color: white;
+    background: #d40 linear-gradient(-45deg,
+        rgba(255, 255, 255, 0.2) 0%,
+        rgba(255, 255, 255, 0.2) 25%,
+        transparent 25%,
+        transparent 50%,
+        rgba(255, 255, 255, 0.2) 50%,
+        rgba(255, 255, 255, 0.2) 75%,
+        transparent 75%,
+        transparent
+    );
+    background-size: 28px 28px;
+}
+.scv-banner > a {
+    color: white;
+}
+
+
+.scv-sphinx_rtd_theme {
+    background-color: #2980B9;
+}
+
+
+.scv-bizstyle {
+    background-color: #336699;
+}
+
+
+.scv-classic {
+    text-align: center !important;
+}
+
+
+.scv-traditional {
+    text-align: center !important;
+}

docs/_templates/page.html

@@ -0,0 +1,17 @@
+{% extends "!page.html" %}
+{% block body %}
+{% if current_version and latest_version and current_version != latest_version %}
+<p class="scv-banner scv-sphinx_rtd_theme">
+  <strong>
+    {% if current_version.is_released %}
+    You're reading an old version of this documentation.
+    If you want up-to-date information, please have a look at <a href="{{ vpathto(latest_version.name) }}">{{latest_version.name}}</a>.
+    {% else %}
+    You're reading the documentation for a development version.
+    For the latest released version, please have a look at <a href="{{ vpathto(latest_version.name) }}">{{latest_version.name}}</a>.
+    {% endif %}
+  </strong>
+</p>
+{% endif %}
+{{ super() }}
+{% endblock %}%

docs/_templates/versions.html

@@ -0,0 +1,27 @@
+{%- if current_version %}
+<div class="rst-versions" data-toggle="rst-versions" role="note" aria-label="versions">
+  <span class="rst-current-version" data-toggle="rst-current-version">
+    <span class="fa fa-book"> Other Versions</span>
+    v: {{ current_version.name }}
+    <span class="fa fa-caret-down"></span>
+  </span>
+  <div class="rst-other-versions">
+    {%- if versions.tags %}
+    <dl>
+      <dt>Tags</dt>
+      {%- for item in versions.tags %}
+      <dd><a href="{{ item.url }}">{{ item.name }}</a></dd>
+      {%- endfor %}
+    </dl>
+    {%- endif %}
+    {%- if versions.branches %}
+    <dl>
+      <dt>Branches</dt>
+      {%- for item in versions.branches %}
+      <dd><a href="{{ item.url }}">{{ item.name }}</a></dd>
+      {%- endfor %}
+    </dl>
+    {%- endif %}
+  </div>
+</div>
+{%- endif %}

docs/changelog.rst

@@ -16,18 +16,121 @@ Changelog
 The changelog summarizes bugfixes that are deemed relevant for users and package maintainers.
 Developers should consult the git commit log or GitHub issue tracker.
 
-We use the following annotations for classifying changes:
+Next Release
+------------
 
-* |break_config| Change that breaks the config.
-  As a package maintainer, make sure to warn your users about config breakage somehow.
-* |break| Change that breaks interoperability or persistent state representation with previous releases.
-  As a package maintainer, make sure to warn your users about config breakage somehow.
-  Note that even updating the package on both sides might not be sufficient, e.g. if persistent state needs to be migrated to a new format.
-* |mig| Migration that must be run by the user.
-* |feature| Change that introduces new functionality.
-* |bugfix| Change that fixes a bug, no regressions or incompatibilities expected.
-* |docs| Change to the documentation.
-* |maint| Maintenance changes.
+The plan for the next release is to revisit how zrepl does snapshot management.
+High-level goals:
+
+- Make it easy to decouple snapshot management (snapshotting, pruning) from replication.
+- Ability to include/exclude snapshots from replication.
+  This is useful for aforementioned decoupling, e.g., separate snapshot prefixes for local & remote replication.
+  Also, it makes explicit that by default, zrepl replicates all snapshots, and that
+  replication has no concept of "zrepl-created snapshots", which is a common misconception.
+- Use of ``zfs snapshot`` comma syntax or channel programs to take snapshots of multiple
+  datasets atomically.
+- Provide an alternative to the ``grid`` pruning policy.
+  Most likely something based on hourly/daily/weekly/monthly "trains" plus a count.
+- Ability to prune at the granularity of the **group** of snapshots created at a given
+  time, as opposed to the individual snapshots within a dataset.
+  Maybe this will be addressed by the alternative to the ``grid`` pruning policy,
+  as it will likely be more predictable.
+
+Those changes will likely come with some breakage in the config.
+However, I want to avoid breaking **use cases** that are satisfied by the current design.
+There will be beta/RC releases to give users a chance to evaluate.
+
+0.6.1
+-----
+
+* |feature| add metric to detect filesystems rules that don't match any local dataset (thanks, `@gmekicaxcient <https://github.com/gmekicaxcient>`_).
+* |bugfix| ``zrepl status``: hide progress bar once all filesystems reach terminal state (thanks, `@0x3333 <https://github.com/0x3333>`_).
+* |bugfix| handling of tenative cursor presence if protection strategy doesn't use it (:issue:`714`).
+* |docs| address setup with two or more external disks (thanks, `@se-jaeger <https://github.com/se-jaeger>`_).
+* |docs| document ``replication`` and ``conflict_resolution`` options (thanks, `@InsanePrawn <https://github.com/InsanePrawn>`_).
+* |docs| docs: talks: add note on keep_bookmarks option (thanks, `@skirmess <https://github.com/skirmess>`_).
+* |maint| dist: add openrc service file (thanks, `@gramosg <https://github.com/gramosg>`_).
+* |maint| grafana: update dashboard to Grafana 9.3.6.
+* |maint| run platform tests as part of CI.
+* |maint| build: upgrade to Go 1.21 and update golangci-lint; minimum Go version for builds is now 1.20
+
+.. NOTE::
+  |  zrepl is a spare-time project primarily developed by `Christian Schwarz <https://cschwarz.com>`_.
+  |  You can support maintenance and feature development through one of the following services:
+  |  |Donate via Patreon| |Donate via GitHub Sponsors| |Donate via Liberapay| |Donate via PayPal|
+  |  Note that PayPal processing fees are relatively high for small donations.
+  |  For SEPA wire transfer and **commercial support**, please `contact Christian directly <https://cschwarz.com>`_.
+
+0.6
+---
+
+* |feature| :ref:`Schedule-based snapshotting<job-snapshotting--cron>` using ``cron`` syntax instead of an interval.
+* |feature| Configurable initial replication policy.
+  When a filesystem is first replicated to a receiver, this control whether just the newest
+  snapshot will be replicated vs. all existing snapshots. Learn more :ref:`in the docs <conflict_resolution-initial_replication>`.
+* |feature| Configurable timestamp format for snapshot names via :ref:`timestamp_format<job-snapshotting-timestamp_format>`
+  (Thanks, `@ydylla <https://github.com/ydylla>`_).
+* |feature| Add ``ZREPL_DESTROY_MAX_BATCH_SIZE`` env var (default 0=unlimited)
+  (Thanks, `@3nprob <https://github.com/3nprob>`_).
+* |feature| Add ``zrepl configcheck --skip-cert-check`` flag (Thanks, `@cole-h <https://github.com/cole-h>`_).
+* |bugfix| Fix resuming from interrupted replications that use ``send.raw`` on unencrypted datasets.
+
+  * The send options introduced in zrepl 0.4 allow users to specify additional zfs send flags for zrepl to use.
+    Before this fix, when setting ``send.raw=true`` on a job that replicates unencrypted datasets,
+    zrepl would not allow an interrupted replication to resume.
+    The reason were overly cautious checks to support the ``send.encrypted`` option.
+  * This bugfix removes these checks from the replication planner.
+    This makes ``send.encrypted`` a sender-side-only concern, much like all other ``send.*`` flags.
+  * However, this means that the ``zrepl status`` UI no longer indicates whether a replication step uses encrypted sends or not.
+    The setting is still effective though.
+
+* |break| convert Prometheus metric ``zrepl_version_daemon`` to ``zrepl_start_time`` metric
+
+  * The metric still reports the zrepl version in a label.
+    But the metric *value* is now the Unix timestamp at the time the daemon was started.
+    The Grafana dashboard in :repomasterlink:`dist/grafana` has been updated.
+
+* |bugfix| transient zrepl status error: ``Post "http://unix/status": EOF``
+* |bugfix| don't treat receive-side bookmarks as a replication conflict.
+  This facilitates chaining of replication jobs. See :issue:`490`.
+* |bugfix| workaround for Go/gRPC problem on Illumos where zrepl would
+  crash when using the ``local`` transport type (:issue:`598`).
+* |bugfix| fix active child tasks panic that cold occur during replication plannig (:issue:`193abbe`)
+* |bugfix| ``zrepl status`` off-by-one error in display of completed step count (:commit:`ce6701f`)
+* |bugfix| Allow using day & week units for ``snapshotting.interval`` (:commit:`ffb1d89`)
+* |docs| ``docs/overview`` improvements (Thanks, `@jtagcat <https://github.com/jtagcat>`_).
+* |maint| Update to Go 1.19.
+
+0.5
+---
+
+* |feature| :ref:`Bandwidth limiting <job-send-recv-options--bandwidth-limit>` (Thanks, Prominic.NET, Inc.)
+* |feature| zrepl status: use a ``*`` to indicate which filesystem is currently replicating
+* |feature| include daemon environment variables in zrepl status (currently only in ``--raw``)
+* |bugfix| **fix encrypt-on-receive + placeholders use case** (:issue:`504`)
+
+  * Before this fix, **plain sends** to a receiver with an encrypted ``root_fs`` **could be received unencrypted** if zrepl needed to create placeholders on the receiver.
+  * Existing zrepl users should :ref:`read the docs <job-recv-options--placeholder>` and check ``zfs get -r encryption,zrepl:placeholder PATH_TO_ROOTFS`` on the receiver.
+  * Thanks to `@mologie <https://github.com/mologie>`_ and `@razielgn <https://github.com/razielgn>`_ for reporting and testing!
+
+* |bugfix| Rename mis-spelled :ref:`send option <job-send-options>` ``embbeded_data`` to ``embedded_data``.
+* |bugfix| zrepl status: replication step numbers should start at 1
+* |bugfix| incorrect bandwidth averaging in ``zrepl status``.
+* |bugfix| FreeBSD with OpenZFS 2.0: zrepl would wait indefinitely for zfs send to exit on timeouts.
+* |bugfix| fix ``strconv.ParseInt: value out of range`` bug (and use the control RPCs).
+* |docs| improve description of multiple pruning rules.
+* |docs| document :ref:`platform tests <usage-platform-tests>`.
+* |docs| quickstart: make users aware that prune rules apply to all snapshots.
+* |maint| some platformtests were broken.
+* |maint| FreeBSD: release armv7 and arm64 binaries.
+* |maint| apt repo: update instructions due to ``apt-key`` deprecation.
+
+Note to all users: please read up on the following OpenZFS bugs, as you might be affected:
+
+* `ZFS send/recv with ashift 9->12 leads to data corruption <https://github.com/openzfs/zfs/issues/12762>`_.
+* Various bugs with encrypted send/recv (`Leadership meeting notes <https://openzfs.topicbox.com/groups/developer/T24bdaa2886c6cbf5-Mc039a11c3f1507ea0664817b/december-openzfs-leadership-meeting>`_)
+
+Finally, I'd like to point you to the `GitHub discussion <https://github.com/zrepl/zrepl/discussions/547>`_ about which bugfixes and features should be prioritized in zrepl 0.6 and beyond!
 
 0.4.0
 -----
@@ -53,13 +156,6 @@ The following bugfix in 0.3.1 :issue:`caused problems for some users <400>`:
 
 * |bugfix| pruning: ``grid``:  add all snapshots that do not match the regex to the rule's destroy list.
 
-.. NOTE::
-  |  zrepl is a spare-time project primarily developed by `Christian Schwarz <https://cschwarz.com>`_.
-  |  You can support maintenance and feature development through one of the following services:
-  |  |Donate via Patreon| |Donate via GitHub Sponsors| |Donate via Liberapay| |Donate via PayPal|
-  |  Note that PayPal processing fees are relatively high for small donations.
-  |  For SEPA wire transfer and **commercial support**, please `contact Christian directly <https://cschwarz.com>`_.
-
 0.3.1
 -----
 
@@ -243,7 +339,7 @@ Changes
 * |feature| Proper timeout handling for the :ref:`SSH transport <transport-ssh+stdinserver>`
 
   * |break| Requires Go 1.11 or later.
-  
+
 * |break| |break_config|: mappings are no longer supported
 
   * Receiving sides (``pull`` and ``sink`` job) specify a single ``root_fs``.

docs/conf.py

@@ -1 +0,0 @@
-sphinxconf/conf.py

docs/conf.py

@@ -0,0 +1,187 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+#
+# zrepl documentation build configuration file, created by
+# sphinx-quickstart on Wed Nov  8 22:28:10 2017.
+#
+# This file is execfile()d with the current directory set to its
+# containing dir.
+#
+# Note that not all possible configuration values are present in this
+# autogenerated file.
+#
+# All configuration values have a default; values that are commented out
+# serve to show the default.
+
+# If extensions (or modules to document with autodoc) are in another directory,
+# add these directories to sys.path here. If the directory is relative to the
+# documentation root, use os.path.abspath to make it absolute, like shown here.
+#
+# import os
+# import sys
+# sys.path.insert(0, os.path.abspath('.'))
+
+
+# -- General configuration ------------------------------------------------
+
+# If your documentation needs a minimal Sphinx version, state it here.
+#
+# needs_sphinx = '1.0'
+
+# Add any Sphinx extension module names here, as strings. They can be
+# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
+# ones.
+extensions = ['sphinx.ext.todo',
+    'sphinx.ext.githubpages',
+    'sphinx.ext.extlinks',
+    "sphinx_multiversion",
+]
+
+# suppress_warnings = ['image.nonlocal_uri']
+
+# Add any paths that contain templates here, relative to this directory.
+templates_path = ['./_templates']
+
+# The suffix(es) of source filenames.
+# You can specify multiple suffix as a list of string:
+#
+# source_suffix = ['.rst', '.md']
+source_suffix = '.rst'
+
+# The master toctree document.
+master_doc = 'index'
+
+# General information about the project.
+project = 'zrepl'
+copyright = '2017-2023, Christian Schwarz'
+author = 'Christian Schwarz'
+
+# The version info for the project you're documenting, acts as replacement for
+# |version| and |release|, also used in various other places throughout the
+# built documents.
+#
+# The short X.Y version.
+#version = set by sphinxcontrib-versioning
+# The full version, including alpha/beta/rc tags.
+#release = version
+
+# The language for content autogenerated by Sphinx. Refer to documentation
+# for a list of supported languages.
+#
+# This is also used if you do content translation via gettext catalogs.
+# Usually you set "language" from the command line for these cases.
+language = 'en'
+
+# List of patterns, relative to source directory, that match files and
+# directories to ignore when looking for source files.
+# This patterns also effect to html_static_path and html_extra_path
+exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
+
+# The name of the Pygments (syntax highlighting) style to use.
+pygments_style = 'sphinx'
+
+# If true, `todo` and `todoList` produce output, else they produce nothing.
+todo_include_todos = True
+
+
+# -- Options for HTML output ----------------------------------------------
+
+# The theme to use for HTML and HTML Help pages.  See the documentation for
+# a list of builtin themes.
+#
+html_theme = 'sphinx_rtd_theme'
+
+# Theme options are theme-specific and customize the look and feel of a theme
+# further.  For a list of options available for each theme, see the
+# documentation.
+#
+# html_theme_options = {}
+
+# Add any paths that contain custom static files (such as style sheets) here,
+# relative to this directory. They are copied after the builtin static files,
+# so a file named "default.css" will overwrite the builtin "default.css".
+html_static_path = ['_static']
+
+html_css_files = [
+    'banner.css',
+]
+
+html_logo = '_static/zrepl.svg'
+
+html_context = {
+  # https://github.com/rtfd/sphinx_rtd_theme/issues/205
+  # Add 'Edit on Github' link instead of 'View page source'
+  "display_github": True,
+  "github_user": "zrepl",
+  "github_repo": "zrepl",
+  "github_version": "master",
+  "conf_py_path": "/docs/",
+  "source_suffix": source_suffix,
+}
+
+# -- Options for HTMLHelp output ------------------------------------------
+
+# Output file base name for HTML help builder.
+htmlhelp_basename = 'zrepldoc'
+
+
+# -- Options for LaTeX output ---------------------------------------------
+
+latex_elements = {
+    # The paper size ('letterpaper' or 'a4paper').
+    #
+    # 'papersize': 'letterpaper',
+
+    # The font size ('10pt', '11pt' or '12pt').
+    #
+    # 'pointsize': '10pt',
+
+    # Additional stuff for the LaTeX preamble.
+    #
+    # 'preamble': '',
+
+    # Latex figure (float) alignment
+    #
+    # 'figure_align': 'htbp',
+}
+
+# Grouping the document tree into LaTeX files. List of tuples
+# (source start file, target name, title,
+#  author, documentclass [howto, manual, or own class]).
+latex_documents = [
+    (master_doc, 'zrepl.tex', 'zrepl Documentation',
+     'Christian Schwarz', 'manual'),
+]
+
+
+# -- Options for manual page output ---------------------------------------
+
+# One entry per manual page. List of tuples
+# (source start file, name, description, authors, manual section).
+man_pages = [
+    (master_doc, 'zrepl', 'zrepl Documentation',
+     [author], 1)
+]
+
+
+# -- Options for Texinfo output -------------------------------------------
+
+# Grouping the document tree into Texinfo files. List of tuples
+# (source start file, target name, title, author,
+#  dir menu entry, description, category)
+texinfo_documents = [
+    (master_doc, 'zrepl', 'zrepl Documentation',
+     author, 'zrepl', 'One line description of project.',
+     'Miscellaneous'),
+]
+
+
+# -- Options for the extlinks extension -----------------------------------
+# http://www.sphinx-doc.org/en/stable/ext/extlinks.html
+extlinks = {
+    'issue':('https://github.com/zrepl/zrepl/issues/%s', 'issue #%s'),
+    'repomasterlink':('https://github.com/zrepl/zrepl/blob/master/%s', '%s'),
+    'sampleconf':('https://github.com/zrepl/zrepl/blob/master/config/samples%s', 'config/samples%s'),
+    'commit':('https://github.com/zrepl/zrepl/commit/%s', 'commit %s'),
+        }
+

docs/configuration.rst

@@ -13,6 +13,7 @@ Configuration
     configuration/filter_syntax
     configuration/sendrecvoptions
     configuration/replication
+    configuration/conflict_resolution
     configuration/snapshotting
     configuration/prune
     configuration/logging

docs/configuration/conflict_resolution.rst

@@ -0,0 +1,37 @@
+.. include:: ../global.rst.inc
+
+.. _conflict_resolution-options:
+
+Conflict Resolution Options
+===========================
+
+
+::
+
+   jobs:
+   - type: push
+     filesystems: ...
+     conflict_resolution:
+       initial_replication: most_recent | all | fail # default: most_recent
+
+     ...
+
+.. _conflict_resolution-initial_replication:
+
+
+``initial_replication`` option
+------------------------------
+
+The ``initial_replication`` option determines how many snapshots zrepl replicates if the filesystem has not been replicated before.
+If ``most_recent`` (the default), the initial replication will only transfer the most recent snapshot, while ignoring previous snapshots.
+If all snapshots should be replicated, specify ``all``.
+Use ``fail`` to make replication of the filesystem fail in case there is no corresponding fileystem on the receiver.
+
+For example, suppose there are snapshosts ``tank@1``, ``tank@2``, ``tank@3`` on a sender.
+Then ``most_recent`` will replicate just ``@3``, but ``all`` will replicate ``@1``, ``@2``, and ``@3``.
+
+If initial replication is interrupted, and there is at least one (maybe partial) snapshot on the receiver, zrepl will always resume in **incremental mode**.
+And that is regardless of where the initial replication was interrupted.
+
+For example, if ``initial_replication: all`` and the transfer of ``@1`` is interrupted, zrepl would retry/resume at ``@1``.
+And even if the user changes the config to ``initial_replication: most_recent`` before resuming, **incremental mode** will still resume at ``@1``.

docs/configuration/jobs.rst

@@ -30,6 +30,10 @@ Job Type ``push``
       - |snapshotting-spec|
     * - ``pruning``
       - |pruning-spec|
+    * - ``replication``
+      - |replication-options|
+    * - ``conflict_resolution``
+      - |conflict-resolution-options|
 
 Example config: :sampleconf:`/push.yml`
 
@@ -81,6 +85,10 @@ Job Type ``pull``
         | ``manual`` disables periodic pulling, replication then only happens on :ref:`wakeup <cli-signal-wakeup>`.
     * - ``pruning``
       - |pruning-spec|
+    * - ``replication``
+      - |replication-options|
+    * - ``conflict_resolution``
+      - |conflict-resolution-options|
 
 Example config: :sampleconf:`/pull.yml`
 

docs/configuration/misc.rst

@@ -1,3 +1,5 @@
+.. _miscellaneous:
+
 Miscellaneous
 =============
 
@@ -42,27 +44,3 @@ Interval & duration fields in job definitions, pruning configurations, etc. must
 
     var durationStringRegex *regexp.Regexp = regexp.MustCompile(`^\s*(\d+)\s*(s|m|h|d|w)\s*$`)
     // s = second, m = minute, h = hour, d = day, w = week (7 days)
-
-Super-Verbose Job Debugging
----------------------------
-
-You have probably landed here because you opened an issue on GitHub and some developer told you to do this...
-So just read the annotated comments ;)
-
-::
-
-    job:
-    - name: ...
-      ...
-     # JOB DEBUGGING OPTIONS
-      # should be equal for all job types, but each job implements the debugging itself
-      debug:
-        conn: # debug the io.ReadWriteCloser connection
-          read_dump: /tmp/connlog_read   # dump results of Read() invocations to this file
-          write_dump: /tmp/connlog_write # dump results of Write() invocations to this file
-        rpc: # debug the RPC protocol implementation
-          log: true # log output from rpc layer to the job log
-
-.. ATTENTION::
-
-    Connection dumps will almost certainly contain your or other's private data. Do not share it in a bug report.

docs/configuration/overview.rst

@@ -3,16 +3,17 @@ Overview & Terminology
 ======================
 
 All work zrepl does is performed by the zrepl daemon which is configured in a single YAML configuration file loaded on startup.
-The following paths are considered:
+The following paths are searched, in this order:
 
-* If set, the location specified via the global ``--config`` flag
-* ``/etc/zrepl/zrepl.yml``
-* ``/usr/local/etc/zrepl/zrepl.yml``
+1. The path specified via the global ``--config`` flag
+2. ``/etc/zrepl/zrepl.yml``
+3. ``/usr/local/etc/zrepl/zrepl.yml``
 
-The ``zrepl configcheck`` subcommand can be used to validate the configuration.
-The command will output nothing and exit with zero status code if the configuration is valid.
+``zrepl configcheck`` can be used to validate the configuration.
+If the configuration is valid, it will output nothing and exit with code ``0``.
 The error messages vary in quality and usefulness: please report confusing config errors to the tracking :issue:`155`.
-Full example configs such as in the :ref:`quick-start guides <quickstart-toc>` or the :sampleconf:`/` directory might also be helpful.
+
+Full example configs are available at :ref:`quick-start guides <quickstart-toc>` and :sampleconf:`/`.
 However, copy-pasting examples is no substitute for reading documentation!
 
 Config File Structure
@@ -26,9 +27,8 @@ Config File Structure
      type: push
    - ...
 
-zrepl is configured using a single YAML configuration file with two main sections: ``global`` and ``jobs``.
-The ``global`` section is filled with sensible defaults and is covered later in this chapter.
-The ``jobs`` section is a list of jobs which we are going to explain now.
+A zrepl configuration file is divided in to two main sections: ``global`` and ``jobs``.
+``global`` has sensible defaults. It is covered in :ref:`logging <logging>`, :ref:`monitoring <monitoring>` \& :ref:`miscellaneous <miscellaneous>`.
 
 .. _job-overview:
 
@@ -42,8 +42,7 @@ Jobs are identified by their ``name``, both in log files and the ``zrepl status`
 .. NOTE::
    The job name is persisted in several places on disk and thus :issue:`cannot be changed easily<327>`.
 
-
-Replication always happens between a pair of jobs: one is the **active side**, and one the **passive side**.
+Replication always happens between a pair of jobs: one **active side** and one **passive side**.
 The active side connects to the passive side using a :ref:`transport <transport>` and starts executing the replication logic.
 The passive side responds to requests from the active side after checking its permissions.
 
@@ -72,30 +71,29 @@ How the Active Side Works
 
 The active side (:ref:`push <job-push>` and :ref:`pull <job-pull>` job) executes the replication and pruning logic:
 
-* Wakeup because of finished snapshotting (``push`` job) or pull interval ticker (``pull`` job).
-* Connect to the corresponding passive side using a :ref:`transport <transport>` and instantiate an RPC client.
-* Replicate data from the sending to the receiving side (see below).
-* Prune on sender & receiver.
+1. Wakeup after snapshotting (``push`` job) or pull interval ticker (``pull`` job).
+2. Connect to the passive side and instantiate an RPC client.
+3. Replicate data from the sender to the receiver.
+4. Prune on sender & receiver.
 
 .. TIP::
-  The progress of the active side can be watched live using the ``zrepl status`` subcommand.
+  The progress of the active side can be watched live using ``zrepl status``.
 
 .. _overview-passive-side--client-identity:
 
 How the Passive Side Works
 --------------------------
 
-The passive side (:ref:`sink <job-sink>` and :ref:`source <job-source>`) waits for connections from the corresponding active side,
-using the transport listener type specified in the ``serve`` field of the job configuration.
-When a client connects, the transport listener performS listener-specific access control (cert validation, IP ACLs, etc)
-and determines the *client identity*.
-The passive side job then uses this client identity as follows:
+The passive side (:ref:`sink <job-sink>` and :ref:`source <job-source>`) waits for connections from the active side,
+on the :ref:`transport <transport>` specified with ``serve`` in the job configuration.
+The respective transport then perfoms authentication & authorization, resulting in a stable *client identity*.
+The passive side job uses this *client identity* as follows:
 
-* The ``sink`` job maps requests from different client identities to their respective sub-filesystem tree ``root_fs/${client_identity}``.
-* The ``source`` might, in the future, embed the client identity in :ref:`zrepl's ZFS abstraction names <zrepl-zfs-abstractions>` in order to support multi-host replication.
+   * In ``sink`` jobs, to map requests from different *client identities* to their respective sub-filesystem tree ``root_fs/${client_identity}``.
+   * *In the future, ``source`` might embed the client identity in :ref:`zrepl's ZFS abstraction names <zrepl-zfs-abstractions>`, to support multi-host replication.*
 
 .. TIP::
-   The implementation of the ``sink`` job requires that the connecting client identities be a valid ZFS filesystem name components.
+   The use of the client identity in the ``sink`` job implies that it must be usable as a ZFS ZFS filesystem name component.
 
 .. _overview-how-replication-works:
 
@@ -106,7 +104,7 @@ One of the major design goals of the replication module is to avoid any duplicat
 As such, the code works on abstract senders and receiver **endpoints**, where typically one will be implemented by a local program object and the other is an RPC client instance.
 Regardless of push- or pull-style setup, the logic executes on the active side, i.e. in the ``push`` or ``pull`` job.
 
-The following high-level steps take place during replication and can be monitored using the ``zrepl status`` subcommand:
+The following high-level steps take place during replication and can be monitored using ``zrepl status``:
 
 * Plan the replication:
 
@@ -132,7 +130,7 @@ The following high-level steps take place during replication and can be monitore
   * Move the **replication cursor** bookmark on the sending side (see below).
   * Move the **last-received-hold** on the receiving side (see below).
   * Release the send-side step-holds.
-   
+
 The idea behind the execution order of replication steps is that if the sender snapshots all filesystems simultaneously at fixed intervals, the receiver will have all filesystems snapshotted at time ``T1`` before the first snapshot at ``T2 = T1 + $interval`` is replicated.
 
 ZFS Background Knowledge
@@ -233,22 +231,11 @@ The ``zrepl zfs-abstraction list`` command provides a listing of all bookmarks a
 
     More details can be found in the design document :repomasterlink:`replication/design.md`.
 
-Limitations
-^^^^^^^^^^^
 
-.. ATTENTION::
+Caveats With Complex Setups (More Than 2 Jobs or Machines)
+----------------------------------------------------------
 
-    Currently, zrepl does not replicate filesystem properties.
-    When receiving a filesystem, it is never mounted (`-u` flag)  and `mountpoint=none` is set.
-    This is temporary and being worked on :issue:`24`.
-
-
-.. _jobs-multiple-jobs:
-
-Multiple Jobs & More than 2 Machines
-------------------------------------
-
-The quick-start guides focus on simple setups with a single sender and a single receiver.
+Most users are served well with a single sender and a single receiver job.
 This section documents considerations for more complex setups.
 
 .. ATTENTION::
@@ -262,7 +249,7 @@ This section documents considerations for more complex setups.
 
    If you can't find your desired configuration, have questions or would like to see improvements to multi-job setups, please `open an issue on GitHub <https://github.com/zrepl/zrepl/issues/new>`_.
 
-Multiple Jobs on one Machine
+Multiple Jobs on One Machine
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 As a general rule, multiple jobs configured on one machine **must operate on disjoint sets of filesystems**.
 Otherwise, concurrently running jobs might interfere when operating on the same filesystem.
@@ -271,6 +258,9 @@ On your setup, ensure that
 
 * all ``filesystems`` filter specifications are disjoint
 * no ``root_fs`` is a prefix or equal to another ``root_fs``
+
+  * For ``sink`` jobs, consider all possible ``root_fs/${client_identity}``.
+
 * no ``filesystems`` filter matches any ``root_fs``
 
 **Exceptions to the rule**:
@@ -281,18 +271,53 @@ On your setup, ensure that
   This scenario is detailed in one of the :ref:`quick-start guides <quickstart-backup-to-external-disk>`.
 
 
-More Than 2 Machines
+Two Or More Machines
 ^^^^^^^^^^^^^^^^^^^^
 
 This section might be relevant to users who wish to *fan-in* (N machines replicate to 1) or *fan-out* (replicate 1 machine to N machines).
 
 **Working setups**:
 
-* N ``push`` identities, 1 ``sink`` (as long as the different push jobs have a different :ref:`client identity <overview-passive-side--client-identity>`)
+* **Fan-in: N servers replicated to one receiver, disjoint dataset trees.**
 
-  * ``sink`` constrains each client to a disjoint sub-tree of the sink-side dataset hierarchy ``${root_fs}/${client_identity}``.
+  * This is the common use case of a centralized backup server.
+
+  * Implementation:
+
+    * N ``push`` jobs (one per sender server), 1 ``sink`` (as long as the different push jobs have a different :ref:`client identity <overview-passive-side--client-identity>`)
+    * N ``source`` jobs (one per sender server), N ``pull`` on the receiver server (unique names, disjoint  ``root_fs``)
+
+  * The ``sink`` job automatically constrains each client to a disjoint sub-tree of the sink-side dataset hierarchy ``${root_fs}/${client_identity}``.
     Therefore, the different clients cannot interfere.
 
+  * The ``pull`` job only pulls from one host, so it's up to the zrepl user to ensure that the different ``pull`` jobs don't interfere.
+
+.. _fan-out-replication:
+
+* **Fan-out: 1 server replicated to N receivers**
+
+  * Can be implemented either in a pull or push fashion.
+
+    * **pull setup**: 1 ``pull`` job on each receiver server, each with a corresponding **unique** ``source`` job on the sender server.
+    * **push setup**: 1 ``sink`` job on each receiver server, each with a corresponding **unique** ``push`` job on the sender server.
+
+  * It is critical that we have one sending-side job (``source``, ``push``) per receiver.
+    The reason is that :ref:`zrepl's ZFS abstractions <zrepl-zfs-abstractions>` (``zrepl zfs-abstraction list``) include the name of the ``source``/``push`` job, but not the receive-side job name or client identity (see :issue:`380`).
+    As a counter-example, suppose we used multiple ``pull`` jobs with only one ``source`` job.
+    All ``pull`` jobs would share the same :ref:`replication cursor bookmark <replication-cursor-and-last-received-hold>` and trip over each other, breaking incremental replication guarantees quickly.
+    The anlogous problem exists for 1 ``push`` to N ``sink`` jobs.
+
+  * The ``filesystems`` matched by the sending side jobs (``source``, ``push``) need not necessarily be disjoint.
+    For this to work, we need to avoid interference between snapshotting and pruning of the different sending jobs.
+    The solution is to centralize sender-side snapshot management in a separate ``snap`` job.
+    Snapshotting in the ``source``/``push`` job should then be disabled (``type: manual``).
+    And sender-side pruning (``keep_sender``) needs to be disabled in the active side (``pull`` / ``push``), since that'll be done by the ``snap job``.
+
+  * **Restore limitations**: when restoring from one of the ``pull`` targets (e.g., using ``zfs send -R``), the replication cursor bookmarks don't exist on the restored system.
+    This can break incremental replication to all other receive-sides after restore.
+
+  * See :ref:`the fan-out replication quick-start guide <quickstart-fan-out-replication>` for an example of this setup.
+
 
 **Setups that do not work**:
 

docs/configuration/prune.rst

@@ -67,8 +67,9 @@ Policy ``not_replicated``
      ...
 
 ``not_replicated`` keeps all snapshots that have not been replicated to the receiving side.
-It only makes sense to specify this rule on a sender (source or push job).
-The state required to evaluate this rule is stored in the :ref:`replication cursor bookmark <replication-cursor-and-last-received-hold>` on the sending side.
+It only makes sense to specify this rule for the ``keep_sender``.
+The reason is that, by definition, all snapshots on the receiver have already been replicated to there from the sender.
+To determine whether a sender-side snapshot has already been replicated, zrepl uses the :ref:`replication cursor bookmark <replication-cursor-and-last-received-hold>` which corresponds to the most recent successfully replicated snapshot.
 
 .. _prune-keep-retention-grid:
 
@@ -106,7 +107,7 @@ The following procedure happens during pruning:
 #. All subsequent buckets are placed adjacent to their predecessor bucket.
 #. Now each snapshot on the axis either falls into one bucket or it is older than our rightmost bucket.
    Buckets are left-inclusive and right-exclusive which means that a snapshot on the edge of bucket will always 'fall into the right one'.
-#. Snapshots older than the rightmost bucket **not kept** by this gridspec.
+#. Snapshots older than the rightmost bucket are **not kept** by the grid specification.
 #. For each bucket, we only keep the ``keep`` oldest snapshots.
 
 The syntax to describe the bucket list is as follows:
@@ -124,43 +125,51 @@ The syntax to describe the bucket list is as follows:
 
 ::
 
-          This grid spec produces the following list of adjacent buckets. For the sake of simplicity,
-          we subject all snapshots to the grid pruning policy by settings `regex: .*`.
+   Assume the following grid specification:
 
-          `
-           grid: 1x1h(keep=all) | 2x2h | 1x3h
-           regex: .*
-          `
+      grid: 1x1h(keep=all) | 2x2h | 1x3h
 
-          0h        1h        2h        3h        4h        5h        6h        7h        8h        9h
-          |         |         |         |         |         |         |         |         |         |
-          |-Bucket1-|-----Bucket 2------|------Bucket 3-----|-----------Bucket 4----------|
-          | keep=all|      keep=1       |       keep=1      |            keep=1           |
+   This grid specification produces the following constellation of buckets:
+
+   0h        1h        2h        3h        4h        5h        6h        7h        8h        9h
+   |         |         |         |         |         |         |         |         |         |
+   |-Bucket1-|-----Bucket2-------|------Bucket3------|-----------Bucket4-----------|
+   | keep=all|      keep=1       |       keep=1      |            keep=1           |
 
 
 
-          Let us consider the following set of snapshots @a-zA-C:
+   Now assume that we have a set of snapshots @a, @b, ..., @D.
+   Snapshot @a is the most recent snapshot.
+   Snapshot @D is the oldest snapshot, it is almost 9 hours older than snapshot @a.
+   We place the snapshots on the same timeline as the buckets:
 
 
-          |  a  b  c  d  e  f  g  h  i  j  k  l  m  n  o  p  q  r  s  t  u  v  w  x  y  z  A  B  C  D        |
+   0h        1h        2h        3h        4h        5h        6h        7h        8h        9h
+   |         |         |         |         |         |         |         |         |         |
+   |-Bucket1-|-----Bucket2-------|------Bucket3------|-----------Bucket4-----------|
+   | keep=all|      keep=1       |       keep=1      |            keep=1           |
+   |         |                   |                   |                             |
+   | a  b  c | d  e  f  g  h  i  j  k  l  m  n  o  p |q  r  s  t  u  v  w  x  y  z |A  B  C  D
 
-          The `grid` algorithm maps them to their respective buckets:
+   We obtain the following mapping of snapshots to buckets:
 
-          Bucket 1: a, b, c
-          Bucket 2: d,e,f,g,h,i,j
-          Bucket 3: k,l,m,n,o,p
-          Bucket 4: q,r, q,r,s,t,u,v,w,x,y,z
-          None:     A,B,C,D
+   Bucket1:   a,b,c
+   Bucket2:   d,e,f,g,h,i
+   Bucket3:   j,k,l,m,n,o,p
+   Bucket4:   q,r,s,t,u,v,w,x,y,z
+   No bucket: A,B,C,D
 
-          It then applies the per-bucket pruning logic described above which resulting in the
-          following list of remaining snapshots.
+   For each bucket, we now prune snapshots until it only contains `keep` snapshots.
+   Newer snapshots are destroyed first.
+   Snapshots that do not fall into a bucket are always destroyed.
 
-          |  a  b  c                    j                 p                             z                    |
-
-          Note that it only makes sense to grow (not shorten) the interval duration for buckets
-          further in the past since each bucket acts like a low-pass filter for incoming snapshots
-          and adding a less-low-pass-filter after a low-pass one has no effect.
+   Result after pruning:
 
+   0h        1h        2h        3h        4h        5h        6h        7h        8h        9h
+   |         |         |         |         |         |         |         |         |         |
+   |-Bucket1-|-----Bucket2-------|------Bucket3------|-----------Bucket4-----------|
+   |         |                   |                   |                             |
+   | a  b  c |                i  |                 p |                           z |
 
 .. _prune-keep-last-n:
 

docs/configuration/replication.rst

@@ -1,5 +1,6 @@
 .. include:: ../global.rst.inc
 
+.. _replication-options:
 
 Replication Options
 ===================

docs/configuration/sendrecvoptions.rst

@@ -36,9 +36,12 @@ See the `upstream man page <https://openzfs.github.io/openzfs-docs/man/8/zfs-sen
     * - ``encrypted``
       -
       - Specific to zrepl, :ref:`see below <job-send-options-encrypted>`.
+    * - ``bandwidth_limit``
+      -
+      - Specific to zrepl, :ref:`see below <job-send-recv-options--bandwidth-limit>`.
     * - ``raw``
       - ``-w``
-      - Use ``encrypted`` to only allow encrypted sends.
+      - Use ``encrypted`` to only allow encrypted sends. Mixed sends are not supported.
     * - ``send_properties``
       - ``-p``
       - **Be careful**, read the :ref:`note on property replication below <job-note-property-replication>`.
@@ -51,7 +54,7 @@ See the `upstream man page <https://openzfs.github.io/openzfs-docs/man/8/zfs-sen
     * - ``compressed``
       - ``-c``
       -
-    * - ``embbeded_data``
+    * - ``embedded_data``
       - ``-e``
       -
     * - ``saved``
@@ -138,8 +141,16 @@ Recv Options
          override: {
            "org.openzfs.systemd:ignore": "on"
          }
+       bandwidth_limit: ...
+       placeholder:
+         encryption: unspecified | off | inherit
      ...
 
+Jump to
+:ref:`properties <job-recv-options--inherit-and-override>` ,
+:ref:`bandwidth_limit <job-send-recv-options--bandwidth-limit>` , and
+:ref:`placeholder <job-recv-options--placeholder>`.
+
 .. _job-recv-options--inherit-and-override:
 
 ``properties``
@@ -186,11 +197,8 @@ Mount behaviour
 * ``canmount``
 * ``overlay``
 
-Note: inheriting or overriding the ``mountpoint`` property on ZVOLs fails in ``zfs recv``.
-This is an `issue in OpenZFS <https://github.com/openzfs/zfs/issues/11416>`_ .
-As a workaround, consider creating separate zrepl jobs for your ZVOL and filesystem datasets.
-Please comment at zrepl :issue:`430` if you encounter this issue and/or would like zrepl to automatically work around it.
-
+Note: Before `OpenZFS 2.0.5 <https://github.com/openzfs/zfs/issues/11416>`_, inheriting or overriding the ``mountpoint`` property on ZVOLs fails in ``zfs recv``.
+If you are on such an older version, consider creating separate zrepl jobs for your ZVOL and filesystem datasets.
 
 Systemd
 -------
@@ -212,3 +220,60 @@ and property replication is enabled, the receiver must :ref:`inherit the followi
 * ``keylocation``
 * ``keyformat``
 * ``encryption``
+
+.. _job-recv-options--placeholder:
+
+Placeholders
+~~~~~~~~~~~~
+
+::
+
+   placeholder:
+     encryption: unspecified | off | inherit
+
+During replication, zrepl :ref:`creates placeholder datasets <replication-placeholder-property>` on the receiving side if the sending side's ``filesystems`` filter creates gaps in the dataset hierarchy.
+This is generally fully transparent to the user.
+However, with OpenZFS Native Encryption, placeholders require zrepl user attention.
+Specifically, the problem is that, when zrepl attempts to create the placeholder dataset on the receiver, and that placeholder's parent dataset is encrypted, ZFS wants to inherit encryption to the placeholder.
+This is relevant to two use cases that zrepl supports:
+
+1. **encrypted-send-to-untrusted-receiver** In this use case, the sender sends an :ref:`encrypted send stream <job-send-options-encrypted>` and the receiver doesn't have the key loaded.
+2. **send-plain-encrypt-on-receive** The receive-side ``root_fs`` dataset is encrypted, and the senders are unencrypted.
+   The key of ``root_fs`` is loaded, and the goal is that the plain sends (e.g., from production) are encrypted on-the-fly during receive, with ``root_fs``'s key.
+
+For **encrypted-send-to-untrusted-receiver**, the placeholder datasets need to be created with ``-o encryption=off``.
+Without it, creation would fail with an error, indicating that the placeholder's parent dataset's key needs to be loaded.
+But we don't trust the receiver, so we can't expect that to ever happen.
+
+However, for **send-plain-encrypt-on-receive**, we cannot set ``-o encryption=off``.
+The reason is that if we did, any of the (non-placeholder) child datasets below the placeholder would inherit ``encryption=off``, thereby silently breaking our encrypt-on-receive use case.
+So, to cover this use case, we need to create placeholders without specifying ``-o encryption``.
+This will make ``zfs create`` inherit the encryption mode from the parent dataset, and thereby transitively from ``root_fs``.
+
+The zrepl config provides the `recv.placeholder.encryption` knob to control this behavior.
+In ``undefined`` mode (default), placeholder creation bails out and asks the user to configure a behavior.
+In ``off`` mode, the placeholder is created with ``encryption=off``, i.e., **encrypted-send-to-untrusted-rceiver** use case.
+In ``inherit`` mode, the placeholder is created without specifying ``-o encryption`` at all, i.e., the **send-plain-encrypt-on-receive** use case.
+
+
+Common Options
+~~~~~~~~~~~~~~
+
+.. _job-send-recv-options--bandwidth-limit:
+
+Bandwidth Limit (send & recv)
+-----------------------------
+
+::
+
+   bandwidth_limit:
+     max: 23.5 MiB # -1 is the default and disabled rate limiting
+     bucket_capacity: # token bucket capacity in bytes; defaults to 128KiB
+
+Both ``send`` and ``recv`` can be limited to a maximum bandwidth through ``bandwidth_limit``.
+For most users, it should be sufficient to just set ``bandwidth_limit.max``.
+The ``bandwidth_limit.bucket_capacity`` refers to the `token bucket size <https://github.com/juju/ratelimit>`_.
+
+The bandwidth limit only applies to the payload data, i.e., the ZFS send stream.
+It does not account for transport protocol overheads.
+The scope is the job level, i.e., all :ref:`concurrent <replication-option-concurrency>` sends or incoming receives of a job share the bandwidth limit.

docs/configuration/snapshotting.rst

@@ -5,53 +5,138 @@
 Taking Snaphots
 ===============
 
-The ``push``, ``source`` and ``snap`` jobs can automatically take periodic snapshots of the filesystems matched by the ``filesystems`` filter field.
-The snapshot names are composed of a user-defined prefix followed by a UTC date formatted like ``20060102_150405_000``.
-We use UTC because it will avoid name conflicts when switching time zones or between summer and winter time.
+You can configure zrepl to take snapshots of the filesystems in the ``filesystems`` field specified in ``push``, ``source`` and ``snap`` jobs.
 
-When a job is started, the snapshotter attempts to get the snapshotting rhythms of the matched ``filesystems`` in sync because snapshotting all filesystems at the same time results in a more consistent backup.
-To find that sync point, the most recent snapshot, made by the snapshotter, in any of the matched ``filesystems`` is used.
-A filesystem that does not have snapshots by the snapshotter has lower priority than filesystem that do, and thus might not be snapshotted (and replicated) until it is snapshotted at the next sync point.
+The following snapshotting types are supported:
 
-For ``push`` jobs, replication is automatically triggered after all filesystems have been snapshotted.
 
-Note that the ``zrepl signal wakeup JOB`` subcommand does not trigger snapshotting.
+.. list-table::
+    :widths: 20 70
+    :header-rows: 1
 
+    * - ``snapshotting.type``
+      - Comment
+    * - ``periodic``
+      - Ensure that snapshots are taken at a particular interval.
+    * - ``cron``
+      - Use cron spec to take snapshots at particular points in time.
+    * - ``manual``
+      - zrepl does not take any snapshots by itself.
+
+The ``periodic`` and ``cron`` snapshotting types share some common options and behavior:
+
+* **Naming:** The snapshot names are composed of a user-defined ``prefix`` followed by a UTC date formatted like ``20060102_150405_000``.
+  We use UTC because it will avoid name conflicts when switching time zones or between summer and winter time.
+* **Hooks:** You can configure hooks to run before or after zrepl takes the snapshots. See :ref:`below <job-snapshotting-hooks>` for details.
+* **Push replication:** After creating all snapshots, the snapshotter will wake up the replication part of the job, if it's a ``push`` job.
+  Note that snapshotting is decoupled from replication, i.e., if it is down or takes too long, snapshots will still be taken.
+  Note further that other jobs are not woken up by snapshotting.
+
+.. NOTE::
+
+   There is **no concept of ownership** of the snapshots that are created by ``periodic`` or ``cron``.
+   Thus, there is no distinction between zrepl-created snapshots and user-created snapshots during replication or pruning.
+
+   In particular, pruning will take all snapshots into consideration by default.
+   To constrain pruning to just zrepl-created snapshots:
+
+     1. Assign a unique `prefix` to the snapshotter and
+     2. Use the ``regex`` functionality of the various pruning ``keep`` rules to just consider snapshots with that prefix.
+
+  There is currently no way to constrain replication to just zrepl-created snapshots.
+  Follow and comment at :issue:`403` if you need this functionality.
+
+.. NOTE::
+
+  The ``zrepl signal wakeup JOB`` subcommand does not trigger snapshotting.
+
+``periodic`` Snapshotting
+-------------------------
 
 ::
 
-    jobs:
-    - type: push
-      filesystems: {
-        "<": true,
-        "tmp": false
-      }
-      snapshotting:
-        type: periodic
-        prefix: zrepl_
-        interval: 10m
-        hooks: ...
-      ...
+   jobs:
+   - ...
+     filesystems: { ... }
+     snapshotting:
+       type: periodic
+       prefix: zrepl_
+       interval: 10m
+       # Timestamp format that is used as snapshot suffix.
+       # Can be any of "dense" (default), "human", "iso-8601", "unix-seconds" or a custom Go time format (see https://go.dev/src/time/format.go)
+       timestamp_format: dense
+       hooks: ...
+    pruning: ...
 
-There is also a ``manual`` snapshotting type, which covers the following use cases:
+The ``periodic`` snapshotter ensures that snapshots are taken in the specified ``interval``.
+If you use zrepl for backup, this translates into your recovery point objective (RPO).
+To meet your RPO, you still need to monitor that replication, which happens asynchronously to snapshotting, actually works.
 
-* Existing infrastructure for automatic snapshots: you only want to use this zrepl job for replication.
-* Handling snapshotting through a separate ``snap`` job.
+It is desirable to get all ``filesystems`` snapshotted simultaneously because it results in a more consistent backup.
+To accomplish this while still maintaining the ``interval``, the ``periodic`` snapshotter attempts to get the snapshotting rhythms in sync.
+To find that sync point, the most recent snapshot, created by the snapshotter, in any of the matched ``filesystems`` is used.
+A filesystem that does not have snapshots by the snapshotter has lower priority than filesystem that do, and thus might not be snapshotted (and replicated) until it is snapshotted at the next sync point.
+The snapshotter uses the ``prefix`` to identify which snapshots it created.
 
-Note that you will have to trigger replication manually using the ``zrepl signal wakeup JOB`` subcommand in that case.
+.. _job-snapshotting--cron:
+
+``cron`` Snapshotting
+---------------------
+
+::
+
+   jobs:
+   - type: snap
+     filesystems: { ... }
+     snapshotting:
+       type: cron
+       prefix: zrepl_
+       # (second, optional) minute hour day-of-month month day-of-week
+       # This example takes snapshots daily at 3:00.
+       cron: "0 3 * * *"
+       # Timestamp format that is used as snapshot suffix.
+       # Can be any of "dense" (default), "human", "iso-8601", "unix-seconds" or a custom Go time format (see https://go.dev/src/time/format.go)
+       timestamp_format: dense
+     pruning: ...
+
+In ``cron`` mode, the snapshotter takes snaphots at fixed points in time.
+See https://en.wikipedia.org/wiki/Cron for details on the syntax.
+zrepl uses the ``the github.com/robfig/cron/v3`` Go package for parsing.
+An optional field for "seconds" is supported to take snapshots at sub-minute frequencies.
+
+.. _job-snapshotting-timestamp_format:
+
+Timestamp Format
+~~~~~~~~~~~~~~~~
+
+The ``cron`` and ``periodic`` snapshotter support configuring a custom timestamp format that is used as suffix for the snapshot name.
+It can be used by setting ``timestamp_format`` to any of the following values:
+
+* ``dense`` (default) looks like ``20060102_150405_000``
+* ``human`` looks like ``2006-01-02_15:04:05``
+* ``iso-8601`` looks like ``2006-01-02T15:04:05.000Z``
+* ``unix-seconds`` looks like ``1136214245``
+* Any custom Go time format accepted by `time.Time#Format <https://go.dev/src/time/format.go>`_.
+
+
+``manual`` Snapshotting
+-----------------------
 
 ::
 
    jobs:
    - type: push
-     filesystems: {
-       "<": true,
-       "tmp": false
-     }
      snapshotting:
        type: manual
      ...
 
+In ``manual`` mode, zrepl does not take snapshots by itself.
+Manual snapshotting is most useful if you have existing infrastructure for snapshot management.
+Or, if you want to decouple snapshot management from replication using a zrepl ``snap`` job.
+See :ref:`this quickstart guide <quickstart-backup-to-external-disk>` for an example.
+
+To trigger replication after taking snapshots, use the ``zrepl signal wakeup JOB`` command.
+
 .. _job-snapshotting-hooks:
 
 Pre- and Post-Snapshot Hooks

docs/global.rst.inc

@@ -5,7 +5,7 @@
 
 .. |GitHub license| image:: https://img.shields.io/github/license/zrepl/zrepl.svg
    :target: https://github.com/zrepl/zrepl/blob/master/LICENSE
-.. |Language: Go| image:: https://img.shields.io/badge/language-Go-6ad7e5.svg
+.. |Language: Go| image:: https://img.shields.io/badge/lang-Go-6ad7e5.svg
    :target: https://golang.org/
 .. |User Docs| image:: https://img.shields.io/badge/docs-web-blue.svg
    :target: https://zrepl.github.io
@@ -13,18 +13,21 @@
    :target: https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=R5QSXJVYHGX96
 .. |Donate via Liberapay| image:: https://img.shields.io/liberapay/patrons/zrepl.svg?logo=liberapay
    :target: https://liberapay.com/zrepl/donate
-.. |Donate via Patreon| image:: https://img.shields.io/badge/dynamic/json?color=yellow&label=Patreon&query=data.attributes.patron_count&suffix=%20patrons&url=https%3A%2F%2Fwww.patreon.com%2Fapi%2Fcampaigns%2F3095079
+.. |Donate via Patreon| image:: https://img.shields.io/badge/dynamic/json?color=yellow&label=Patreon&query=data.attributes.patron_count&url=https%3A%2F%2Fwww.patreon.com%2Fapi%2Fcampaigns%2F3095079
    :target: https://www.patreon.com/zrepl
 .. |Donate via GitHub Sponsors| image:: https://img.shields.io/static/v1?label=Sponsor&message=%E2%9D%A4&logo=GitHub&style=flat&color=yellow
    :target: https://github.com/sponsors/problame
 .. |Twitter| image:: https://img.shields.io/twitter/url/https/github.com/zrepl/zrepl.svg?style=social
    :target: https://twitter.com/intent/tweet?text=Wow:&url=https%3A%2F%2Fgithub.com%2Fzrepl%2Fzrepl
-
+.. |Matrix| image:: https://img.shields.io/badge/chat-matrix-blue.svg
+   :target: https://matrix.to/#/#zrepl:matrix.org
 
 .. |serve-transport| replace:: :ref:`serve specification<transport>`
 .. |connect-transport| replace:: :ref:`connect specification<transport>`
 .. |send-options| replace:: :ref:`send options<job-send-options>`, e.g. for encrypted sends
 .. |recv-options| replace:: :ref:`recv options<job-recv-options>`
+.. |replication-options| replace:: :ref:`replication options<replication-options>`
+.. |conflict-resolution-options| replace:: :ref:`conflict resolution options<conflict_resolution-options>`
 .. |snapshotting-spec| replace:: :ref:`snapshotting specification <job-snapshotting-spec>`
 .. |pruning-spec| replace:: :ref:`pruning specification <prune>`
 .. |filter-spec| replace:: :ref:`filter specification<pattern-filter>`

docs/index.rst

@@ -5,7 +5,7 @@
 
 .. include:: global.rst.inc
 
-|GitHub license| |Language: Go| |Twitter| |Donate via Patreon| |Donate via GitHub Sponsors| |Donate via Liberapay| |Donate via PayPal|
+|GitHub license| |Language: Go| |Twitter| |Donate via Patreon| |Donate via GitHub Sponsors| |Donate via Liberapay| |Donate via PayPal| |Matrix|
 
 
 zrepl - ZFS replication
@@ -25,10 +25,10 @@ zrepl - ZFS replication
          Progress: [=========================\----] 246.7 MiB / 264.7 MiB @ 11.5 MiB/s
            zroot              STEPPING (step 1/2, 624 B/1.2 KiB) next: @a => @b
            zroot/ROOT         DONE (step 2/2, 1.2 KiB/1.2 KiB)
-           zroot/ROOT/default STEPPING (step 1/2, 123.4 MiB/129.3 MiB) next: @a => @b
+         * zroot/ROOT/default STEPPING (step 1/2, 123.4 MiB/129.3 MiB) next: @a => @b
            zroot/tmp          STEPPING (step 1/2, 29.9 KiB/44.2 KiB) next: @a => @b
            zroot/usr          STEPPING (step 1/2, 624 B/1.2 KiB) next: @a => @b
-           zroot/usr/home     STEPPING (step 1/2, 123.3 MiB/135.3 MiB) next: @a => @b
+         * zroot/usr/home     STEPPING (step 1/2, 123.3 MiB/135.3 MiB) next: @a => @b
            zroot/var          STEPPING (step 1/2, 624 B/1.2 KiB) next: @a => @b
            zroot/var/audit    DONE (step 2/2, 1.2 KiB/1.2 KiB)
            zroot/var/crash    DONE (step 2/2, 1.2 KiB/1.2 KiB)
@@ -66,6 +66,7 @@ Main Features
     * [x] Large blocks send & receive
     * [x] Embedded data send & receive
     * [x] Resume state send & receive
+    * [x] Bandwidth limiting
 
 * **Automatic snapshot management**
 
@@ -136,5 +137,6 @@ Table of Contents
    pr
    changelog
    GitHub Repository & Issue Tracker <https://github.com/zrepl/zrepl>
+   Chat: Matrix <https://matrix.to/#/#zrepl:matrix.org>
    supporters
 

docs/installation/apt-repos.rst

@@ -9,18 +9,29 @@ The fingerprint of the signing key is ``E101 418F D3D6 FBCB 9D65  A62D 7086 99FC
 It is available at `<https://zrepl.cschwarz.com/apt/apt-key.asc>`_ .
 Please open an issue in on GitHub if you encounter any issues with the repository.
 
-The following snippet configure the repository for your Debian or Ubuntu release:
-
 ::
 
-    sudo apt update && sudo apt install curl gnupg lsb-release; \
-    ARCH="$(dpkg --print-architecture)"; \
-    CODENAME="$(lsb_release -i -s | tr '[:upper:]' '[:lower:]') $(lsb_release -c -s | tr '[:upper:]' '[:lower:]')"; \
-    echo "Using Distro and Codename: $CODENAME"; \
-    (curl https://zrepl.cschwarz.com/apt/apt-key.asc | sudo apt-key add -) && \
-    (echo "deb [arch=$ARCH] https://zrepl.cschwarz.com/apt/$CODENAME main" | sudo tee /etc/apt/sources.list.d/zrepl.list) && \
-    sudo apt update
+    (
+    set -ex
+    zrepl_apt_key_url=https://zrepl.cschwarz.com/apt/apt-key.asc
+    zrepl_apt_key_dst=/usr/share/keyrings/zrepl.gpg
+    zrepl_apt_repo_file=/etc/apt/sources.list.d/zrepl.list
 
+    # Install dependencies for subsequent commands
+    sudo apt update && sudo apt install curl gnupg lsb-release
+
+    # Deploy the zrepl apt key.
+    curl -fsSL "$zrepl_apt_key_url" | tee | gpg --dearmor | sudo tee "$zrepl_apt_key_dst" > /dev/null
+
+    # Add the zrepl apt repo.
+    ARCH="$(dpkg --print-architecture)"
+    CODENAME="$(lsb_release -i -s | tr '[:upper:]' '[:lower:]') $(lsb_release -c -s | tr '[:upper:]' '[:lower:]')"
+    echo "Using Distro and Codename: $CODENAME"
+    echo "deb [arch=$ARCH signed-by=$zrepl_apt_key_dst] https://zrepl.cschwarz.com/apt/$CODENAME main" | sudo tee /etc/apt/sources.list.d/zrepl.list
+
+    # Update apt repos.
+    sudo apt update
+    )
 
 .. NOTE::
 

docs/installation/freebsd-jail-with-iocage.rst

@@ -93,6 +93,7 @@ Enable the zrepl daemon to start automatically at boot:
 
    sysrc zrepl_enable="YES"
 
+Now jump to :ref:`the summary <installation-freebsd-jail-summary>` below.
 
 Plugin
 ######
@@ -134,7 +135,18 @@ Now ``zrepl`` can be started.
 
    service zrepl start
 
+Now jump to :ref:`the summary <installation-freebsd-jail-summary>` below.
+
+.. _installation-freebsd-jail-summary:
+
 Summary
 -------
 
 Congratulations, you have a working jail!
+
+.. NOTE::
+
+   With FreeBSD 13's transition to OpenZFS 2.0, please ensure that your jail's FreeBSD version matches the one in the kernel module.
+   If you are getting cryptic errors such as
+   ``cannot receive new filesystem stream: invalid backup stream``
+   the instructions posted `here <https://github.com/zrepl/zrepl/issues/500#issuecomment-966215205>`_ might help.

docs/pr.rst

@@ -15,3 +15,5 @@ Talks & Presentations
   `Event <https://wiki.freebsd.org/DevSummit/201709>`__
   )
 
+  * Note: The remarks on ``keep_bookmarks`` are irrelevant as of zrepl 0.1 which introduced the zrepl-managed replication cursor bookmark.
+    Read the `Overview <overview-how-replication-works>`_ section to learn more.

docs/publish.sh

@@ -1,10 +1,10 @@
 #!/bin/bash
-set -eo pipefail
-
+set -euo pipefail
 
 NON_INTERACTIVE=false
 DO_CLONE=false
-while getopts "ca" arg; do
+PUSH=false
+while getopts "caP" arg; do
     case "$arg" in
         "a")
             NON_INTERACTIVE=true
@@ -12,8 +12,11 @@ while getopts "ca" arg; do
         "c")
             DO_CLONE=true
             ;;
+        "P")
+            PUSH=true
+            ;;
         *)
-            echo invalid option
+            echo "invalid option '-$arg'"
             exit 1
             ;;
     esac
@@ -27,13 +30,8 @@ checkout_repo_msg() {
     echo "clone ${GHPAGESREPO} to ${PUBLICDIR}:"
 }
 
-exit_msg() {
-    echo "error, exiting..."
-}
-trap exit_msg EXIT
-
-if ! type sphinx-versioning >/dev/null; then
-    echo "install sphinx-versioning and come back"
+if ! type sphinx-multiversion >/dev/null; then
+    echo "install sphinx-multiversion and come back"
     exit 1
 fi
 
@@ -55,11 +53,11 @@ else
     read -r
 fi
 
-pushd "$PUBLICDIR" 
+pushd "$PUBLICDIR"
 
 echo "verify we're in the GitHub pages repo..."
 git remote get-url origin | grep -E "^${GHPAGESREPO}\$"
-if [ "$?" -ne "0" ] ;then 
+if [ "$?" -ne "0" ] ;then
     checkout_repo_msg
     echo "finished checkout, please run again"
     exit 1
@@ -71,32 +69,39 @@ git reset --hard origin/master
 
 echo "cleaning GitHub pages repo"
 git rm -rf .
+cat > .gitignore <<EOF
+**/.doctrees
+EOF
 
 popd
 
 echo "building site"
 
-flags="$(python3 gen-sphinx-versioning-flags.py)"
-set -e
-sphinx-versioning build \
-   $flags \
-   docs ./public_git \
-   -- -c sphinxconf # older conf.py throw errors because they used
-                    # version = subprocess.show_output(["git", "describe"])
-                    # which fails when building with sphinxcontrib-versioning
-set +e
+python3 run-sphinx-multiversion.py . ./public_git
+
 
 CURRENT_COMMIT=$(git rev-parse HEAD)
 git status --porcelain
 if [[ "$(git status --porcelain)" != "" ]]; then
-    CURRENT_COMMIT="${CURRENT_COMMIT}(dirty)" 
+    CURRENT_COMMIT="${CURRENT_COMMIT}(dirty)"
 fi
-COMMIT_MSG="sphinx-versioning render from publish.sh - $(date -u) - ${CURRENT_COMMIT}"
+COMMIT_MSG="render from publish.sh - $(date -u) - ${CURRENT_COMMIT}"
 
 pushd "$PUBLICDIR"
 
 echo "adding and commiting all changes in GitHub pages repo"
+git add .gitignore
 git add -A
-git commit -m "$COMMIT_MSG"
-git push origin master
+if [ "$(git status --porcelain)" != "" ]; then
+    git commit -m "$COMMIT_MSG"
+else
+    echo "nothing to commit"
+fi
+
+if $PUSH; then
+    echo "pushing to GitHub pages repo"
+    git push origin master
+else
+    echo "not pushing to GitHub pages repo, set -P flag to push"
+fi
 

docs/quickstart.rst

@@ -33,6 +33,7 @@ Keep the :ref:`full config documentation <configuration_toc>` handy if a config
 
    quickstart/continuous_server_backup
    quickstart/backup_to_external_disk
+   quickstart/fan_out_replication
 
 Use ``zrepl configcheck`` to validate your configuration.
 No output indicates that everything is fine.
@@ -51,6 +52,19 @@ We hope that you have found a configuration that fits your use case.
 Use ``zrepl configcheck`` once again to make sure the config is correct (output indicates that everything is fine).
 Then restart the zrepl daemon on all systems involved in the replication, likely using ``service zrepl restart`` or ``systemctl restart zrepl``.
 
+.. WARNING::
+
+   Please :ref:`read up carefully <prune>` on the pruning rules before applying the config.
+   In particular, note that most example configs apply to all snapshots, not just zrepl-created snapshots.
+   Use the following keep rule on sender and receiver to prevent this:
+
+   ::
+      
+      - type: regex
+        negate: true
+        regex: "^zrepl_.*" # <- the 'prefix' specified in snapshotting.prefix
+
+
 Watch it Work
 =============
 

docs/quickstart/backup_to_external_disk.rst

@@ -13,7 +13,7 @@ Thus, we only keep one hour worth of high-resolution snapshots, then fade them o
 
 At the end of each work day, we connect our external disk that serves as our workstation's local offline backup.
 We want zrepl to inspect the filesystems and snapshots on the external pool, figure out which snapshots were created since the last time we connected the external disk, and use incremental replication to efficiently mirror our workstation to our backup disk.
-Afterwards, we want to clean up old snapshots on the backup pool: we want to keep all snapshots younger than one hour, 24 for each hor of the first day, then 360 daily backups.
+Afterwards, we want to clean up old snapshots on the backup pool: we want to keep all snapshots younger than one hour, 24 for each hour of the first day, then 360 daily backups.
 
 A few additional requirements:
 
@@ -33,4 +33,17 @@ You will likely want to customize some aspects mentioned in the top comment in t
 
 .. literalinclude:: ../../config/samples/quickstart_backup_to_external_disk.yml
 
+
+Offline Backups with two (or more) External Disks
+-------------------------------------------------
+
+It can be desirable to have multiple disk-based backups of the same machine.
+To accomplish this,
+
+* create one zpool per external HDD, each with a unique name, and
+* define a pair of ``push`` and ``sink`` job **for each** of these zpools, each with a unique ``name``, ``listener_name``, and ``root_fs``.
+
+The unique names ensure that the jobs don't step on each others' toes when managing :ref:`zrepl's ZFS abstractions <zrepl-zfs-abstractions>` . 
+
+
 :ref:`Click here <quickstart-apply-config>` to go back to the quickstart guide.

docs/quickstart/continuous_server_backup.rst

@@ -9,13 +9,13 @@ This config example shows how we can backup our ZFS-based server to another mach
 
 * Production server ``prod`` with filesystems to back up:
 
-  * ``zroot/var/db``
-  * ``zroot/usr/home`` and all its child filesystems
-  * **except** ``zroot/usr/home/paranoid`` belonging to a user doing backups themselves
+  * The entire pool ``zroot``
+  * except ``zroot/var/tmp`` and all child datasets of it
+  * and except ``zroot/usr/home/paranoid`` which belongs to a user doing backups themselves.
 
-* Backup server ``backups`` with
+* Backup server ``backups`` with a dataset sub-tree for use by zrepl:
 
-  * Filesystem ``storage/zrepl/sink/prod`` + children dedicated to backups of ``prod``
+  * In our example, that will be ``storage/zrepl/sink/prod``.
 
 Our backup solution should fulfill the following requirements:
 

docs/quickstart/fan_out_replication.rst

@@ -0,0 +1,93 @@
+.. include:: ../global.rst.inc
+
+.. _quickstart-fan-out-replication:
+
+Fan-out replication
+===================
+
+This quick-start example demonstrates how to implement a fan-out replication setup where datasets on a server (A) are replicated to multiple targets (B, C, etc.).
+
+This example uses multiple ``source`` jobs on server A and ``pull`` jobs on the target servers.
+
+.. WARNING::
+
+   Before implementing this setup, please see the caveats listed in the :ref:`fan-out replication configuration overview <fan-out-replication>`.
+
+Overview
+--------
+
+On the source server (A), there should be:
+
+* A ``snap`` job
+
+  * Creates the snapshots
+  * Handles the pruning of snapshots
+
+* A ``source`` job for target B
+
+  * Accepts connections from server B and B only
+
+* Further ``source`` jobs for each additional target (C, D, etc.)
+
+  * Listens on a unique port
+  * Only accepts connections from the specific target
+
+On each target server, there should be:
+
+* A ``pull`` job that connects to the corresponding ``source`` job on A
+
+  * ``prune_sender`` should keep all snapshots since A's ``snap`` job handles the pruning
+  * ``prune_receiver`` can be configured as appropriate on each target server
+
+Generate TLS Certificates
+-------------------------
+
+Mutual TLS via the :ref:`TLS client authentication transport <transport-tcp+tlsclientauth>` can be used to secure the connections between the servers. In this example, a self-signed certificate is created for each server without setting up a CA.
+
+.. code-block:: bash
+
+    source=a.example.com
+    targets=(
+        b.example.com
+        c.example.com
+        # ...
+    )
+
+    for server in "${source}" "${targets[@]}"; do
+        openssl req -x509 -sha256 -nodes \
+            -newkey rsa:4096 \
+            -days 365 \
+            -keyout "${server}.key" \
+            -out "${server}.crt" \
+            -addext "subjectAltName = DNS:${server}" \
+            -subj "/CN=${server}"
+    done
+
+    # Distribute each host's keypair
+    for server in "${source}" "${targets[@]}"; do
+        ssh root@"${server}" mkdir /etc/zrepl
+        scp "${server}".{crt,key} root@"${server}":/etc/zrepl/
+    done
+
+    # Distribute target certificates to the source
+    scp "${targets[@]/%/.crt}" root@"${source}":/etc/zrepl/
+
+    # Distribute source certificate to the targets
+    for server in "${targets[@]}"; do
+        scp "${source}.crt" root@"${server}":/etc/zrepl/
+    done
+
+Configure source server A
+-------------------------
+
+.. literalinclude:: ../../config/samples/quickstart_fan_out_replication_source.yml
+
+Configure each target server
+----------------------------
+
+.. literalinclude:: ../../config/samples/quickstart_fan_out_replication_target.yml
+
+Go Back To Quickstart Guide
+---------------------------
+
+:ref:`Click here <quickstart-apply-config>` to go back to the quickstart guide.

docs/requirements.txt

@@ -1,30 +1,24 @@
-alabaster==0.7.12
-attrs==19.1.0
-Babel==2.7.0
-certifi==2019.6.16
-chardet==3.0.4
-Click==7.0
-colorclass==2.2.0
-docutils==0.15.2
-idna==2.8
-imagesize==1.1.0
-Jinja2==2.10.1
-MarkupSafe==1.1.1
-packaging==19.1
-Pygments==2.4.2
-pyparsing==2.4.2
-pytz==2019.2
-requests==2.22.0
-six==1.12.0
-snowballstemmer==1.9.1
-Sphinx==1.8.5
-sphinx-rtd-theme==0.4.3
-sphinxcontrib-applehelp==1.0.1
-sphinxcontrib-devhelp==1.0.1
-sphinxcontrib-htmlhelp==1.0.2
+alabaster==0.7.13
+Babel==2.12.1
+certifi==2023.7.22
+charset-normalizer==3.2.0
+docutils==0.18.1
+idna==3.4
+imagesize==1.4.1
+Jinja2==3.1.2
+MarkupSafe==2.1.3
+packaging==23.1
+Pygments==2.16.1
+requests==2.31.0
+snowballstemmer==2.2.0
+Sphinx==7.2.5
+sphinx-multiversion @ git+https://github.com/zrepl/sphinx-multiversion/@52c915d7ad898d9641ec48c8bbccb7d4f079db93
+sphinx-rtd-theme==1.3.0
+sphinxcontrib-applehelp==1.0.7
+sphinxcontrib-devhelp==1.0.5
+sphinxcontrib-htmlhelp==2.0.4
+sphinxcontrib-jquery==4.1
 sphinxcontrib-jsmath==1.0.1
-sphinxcontrib-qthelp==1.0.2
-sphinxcontrib-serializinghtml==1.1.3
--e git://github.com/rwblair/sphinxcontrib-versioning.git@7e3885a389a809e17ea55261316b7b0e98dbf98f#egg=sphinxcontrib-versioning
-sphinxcontrib-websupport==1.1.2
-urllib3==1.25.3
+sphinxcontrib-qthelp==1.0.6
+sphinxcontrib-serializinghtml==1.1.9
+urllib3==2.0.4

docs/run-sphinx-multiversion.py

@@ -1,7 +1,15 @@
 #!/usr/bin/env python3
 
+from pathlib import Path
 import subprocess
 import re
+import argparse
+import distutils
+
+argparser = argparse.ArgumentParser()
+argparser.add_argument("docsroot")
+argparser.add_argument("outdir")
+args = argparser.parse_args()
 
 output = subprocess.run(["git", "tag", "-l"], capture_output=True, check=True, text=True)
 tagRE = re.compile(r"^v(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)(-rc(?P<rc>\d+))?$")
@@ -27,8 +35,8 @@ for line in output.stdout.split("\n"):
 
     t = Tag()
     t.orig = line
-    t.major = int(m["major"])   
-    t.minor = int(m["minor"])   
+    t.major = int(m["major"])
+    t.minor = int(m["minor"])
     t.patch = int(m["patch"])
     t.rc = int(m["rc"] if m["rc"] is not None else 0)
 
@@ -49,26 +57,16 @@ for (mm, l) in by_major_minor.items():
     latest_by_major_minor.append(l[-1])
 latest_by_major_minor.sort(key=lambda tag: (tag.major, tag.minor))
 
-# print(by_major_minor)
-# print(latest_by_major_minor)
-
-cmdline = []
-
-for latest_patch in latest_by_major_minor:
-    cmdline.append("--whitelist-tags")
-    cmdline.append(f"^{re.escape(latest_patch.orig)}$")
-
-# we want flexibility to update docs for the latest stable release
-# => we have a branch for that, called `stable` which we move manually
-# TODO: in the future, have f"stable-{latest_by_major_minor[-1]}"
-default_version = "stable"
-cmdline.extend(["--whitelist-branches", default_version])
-
-cmdline.extend(["--root-ref", f"{default_version}"])
-cmdline.extend(["--banner-main-ref", f"{default_version}"])
-cmdline.extend(["--show-banner"])
-cmdline.extend(["--sort", "semver"])
-
-cmdline.extend(["--whitelist-branches", "master"])
-
-print(" ".join(cmdline))
+cmdline = [
+    "sphinx-multiversion",
+    "-D", "smv_tag_whitelist=^({})$".format("|".join([re.escape(tag.orig) for tag in latest_by_major_minor])),
+    "-D", "smv_branch_whitelist=^(master|stable)$",
+    "-D", "smv_remote_whitelist=^.*$",
+    "-D", "smv_latest_version=stable",
+    "-D", r"smv_released_pattern=^refs/(tags|heads|remotes/[^/]+)/(?!master).*$", # treat everything except master as released, that way, the banner message makes sense
+    # "--dump-metadata", # for debugging
+    args.docsroot,
+    args.outdir,
+]
+print(cmdline)
+subprocess.run(cmdline, check=True)

docs/sphinxconf/conf.py

@@ -1,182 +0,0 @@
-#!/usr/bin/env python3
-# -*- coding: utf-8 -*-
-#
-# zrepl documentation build configuration file, created by
-# sphinx-quickstart on Wed Nov  8 22:28:10 2017.
-#
-# This file is execfile()d with the current directory set to its
-# containing dir.
-#
-# Note that not all possible configuration values are present in this
-# autogenerated file.
-#
-# All configuration values have a default; values that are commented out
-# serve to show the default.
-
-# If extensions (or modules to document with autodoc) are in another directory,
-# add these directories to sys.path here. If the directory is relative to the
-# documentation root, use os.path.abspath to make it absolute, like shown here.
-#
-# import os
-# import sys
-# sys.path.insert(0, os.path.abspath('.'))
-
-
-# -- General configuration ------------------------------------------------
-
-# If your documentation needs a minimal Sphinx version, state it here.
-#
-# needs_sphinx = '1.0'
-
-# Add any Sphinx extension module names here, as strings. They can be
-# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
-# ones.
-extensions = ['sphinx.ext.todo',
-    'sphinx.ext.githubpages',
-    'sphinx.ext.extlinks']
-
-suppress_warnings = ['image.nonlocal_uri']
-
-# Add any paths that contain templates here, relative to this directory.
-templates_path = ['../_templates']
-
-# The suffix(es) of source filenames.
-# You can specify multiple suffix as a list of string:
-#
-# source_suffix = ['.rst', '.md']
-source_suffix = '.rst'
-
-# The master toctree document.
-master_doc = 'index'
-
-# General information about the project.
-project = 'zrepl'
-copyright = '2017-2019, Christian Schwarz'
-author = 'Christian Schwarz'
-
-# The version info for the project you're documenting, acts as replacement for
-# |version| and |release|, also used in various other places throughout the
-# built documents.
-#
-# The short X.Y version.
-#version = set by sphinxcontrib-versioning
-# The full version, including alpha/beta/rc tags.
-#release = version
-
-# The language for content autogenerated by Sphinx. Refer to documentation
-# for a list of supported languages.
-#
-# This is also used if you do content translation via gettext catalogs.
-# Usually you set "language" from the command line for these cases.
-language = None
-
-# List of patterns, relative to source directory, that match files and
-# directories to ignore when looking for source files.
-# This patterns also effect to html_static_path and html_extra_path
-exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
-
-# The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
-
-# If true, `todo` and `todoList` produce output, else they produce nothing.
-todo_include_todos = True
-
-
-# -- Options for HTML output ----------------------------------------------
-
-# The theme to use for HTML and HTML Help pages.  See the documentation for
-# a list of builtin themes.
-#
-html_theme = 'sphinx_rtd_theme'
-
-# Theme options are theme-specific and customize the look and feel of a theme
-# further.  For a list of options available for each theme, see the
-# documentation.
-#
-# html_theme_options = {}
-
-# Add any paths that contain custom static files (such as style sheets) here,
-# relative to this directory. They are copied after the builtin static files,
-# so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['../_static']
-
-
-html_logo = '../_static/zrepl.svg'
-
-html_context = {
-  # https://github.com/rtfd/sphinx_rtd_theme/issues/205
-  # Add 'Edit on Github' link instead of 'View page source'
-  "display_github": True, 
-  "github_user": "zrepl",
-  "github_repo": "zrepl",
-  "github_version": "master",
-  "conf_py_path": "/docs/",
-  "source_suffix": source_suffix,
-}
-
-# -- Options for HTMLHelp output ------------------------------------------
-
-# Output file base name for HTML help builder.
-htmlhelp_basename = 'zrepldoc'
-
-
-# -- Options for LaTeX output ---------------------------------------------
-
-latex_elements = {
-    # The paper size ('letterpaper' or 'a4paper').
-    #
-    # 'papersize': 'letterpaper',
-
-    # The font size ('10pt', '11pt' or '12pt').
-    #
-    # 'pointsize': '10pt',
-
-    # Additional stuff for the LaTeX preamble.
-    #
-    # 'preamble': '',
-
-    # Latex figure (float) alignment
-    #
-    # 'figure_align': 'htbp',
-}
-
-# Grouping the document tree into LaTeX files. List of tuples
-# (source start file, target name, title,
-#  author, documentclass [howto, manual, or own class]).
-latex_documents = [
-    (master_doc, 'zrepl.tex', 'zrepl Documentation',
-     'Christian Schwarz', 'manual'),
-]
-
-
-# -- Options for manual page output ---------------------------------------
-
-# One entry per manual page. List of tuples
-# (source start file, name, description, authors, manual section).
-man_pages = [
-    (master_doc, 'zrepl', 'zrepl Documentation',
-     [author], 1)
-]
-
-
-# -- Options for Texinfo output -------------------------------------------
-
-# Grouping the document tree into Texinfo files. List of tuples
-# (source start file, target name, title, author,
-#  dir menu entry, description, category)
-texinfo_documents = [
-    (master_doc, 'zrepl', 'zrepl Documentation',
-     author, 'zrepl', 'One line description of project.',
-     'Miscellaneous'),
-]
-
-
-# -- Options for the extlinks extension -----------------------------------
-# http://www.sphinx-doc.org/en/stable/ext/extlinks.html
-extlinks = {
-    'issue':('https://github.com/zrepl/zrepl/issues/%s', 'issue #'),
-    'repomasterlink':('https://github.com/zrepl/zrepl/blob/master/%s', ''),
-    'sampleconf':('https://github.com/zrepl/zrepl/blob/master/config/samples%s', 'config/samples'),
-    'commit':('https://github.com/zrepl/zrepl/commit/%s', 'commit '),
-        }
-

docs/supporters.rst

@@ -32,6 +32,9 @@ We would like to thank the following people and organizations for supporting zre
 
    <div class="fa fa-code" style="width: 1em;"></div>
 
+* |supporter-std| `Max Christian Pohle <https://coderonline.de>`_
+* |supporter-gold| Prominic.NET, Inc.
+* |supporter-std| Torsten Blum
 * |supporter-gold| Cyberiada GmbH
 * |supporter-std| `Gordon Schulz <https://github.com/azmodude>`_
 * |supporter-std| `@jwittlincohen <https://github.com/jwittlincohen>`_

docs/usage.rst

@@ -26,7 +26,7 @@ CLI Overview
     * - ``zrepl daemon``
       - run the daemon, required for all zrepl functionality
     * - ``zrepl status``
-      - show job activity, or with ``--raw`` for JSON output
+      - show job activity, or with ``--mode raw`` for JSON output
     * - ``zrepl stdinserver``
       - see :ref:`transport-ssh+stdinserver`
     * - ``zrepl signal wakeup JOB``
@@ -77,4 +77,74 @@ Systemd Unit File
 
 A systemd service definition template is available in :repomasterlink:`dist/systemd`.
 Note that some of the options only work on recent versions of systemd.
-Any help & improvements are very welcome, see :issue:`145`.
+Any help & improvements are very welcome, see :issue:`145`.
+
+
+
+============
+Ops Runbooks
+============
+
+
+.. toctree::
+
+   usage/runbooks/migrating_sending_side_to_new_zpool.rst
+
+
+.. _usage-platform-tests:
+
+==============
+Platform Tests
+==============
+
+Along with the main ``zrepl`` binary, we release the ``platformtest`` binaries.
+The zrepl platform tests are an integration test suite that is complementary to the pure Go unit tests.
+Any test that needs to interact with ZFS is a platform test.
+
+The platform need to run as root.
+For each test, we create a fresh dummy zpool backed by a file-based vdev.
+The file path, and a root mountpoint for the dummy zpool, must be specified on the command line:
+
+::
+
+   mkdir -p /tmp/zreplplatformtest
+   ./platformtest \
+       -poolname 'zreplplatformtest' \  # <- name must contain zreplplatformtest
+       -imagepath /tmp/zreplplatformtest.img \ # <- zrepl will create the file
+       -mountpoint /tmp/zreplplatformtest # <- must exist
+
+
+.. WARNING::
+
+   ``platformtest`` will unconditionally overwrite the file at `imagepath`
+   and unconditionally ``zpool destroy $poolname``.
+   So, don't use a production poolname, and consider running the test in a VM.
+   It'll be a lot faster as well because the underlying operations, ``zfs list`` in particular, will be faster.
+
+
+While the platformtests are running, there will be a log of log output.
+After all tests have run, it prints a summary with a list of tests, grouped by result type (success, failure, skipped):
+
+::
+
+   PASSING TESTS:
+     github.com/zrepl/zrepl/platformtest/tests.BatchDestroy
+     github.com/zrepl/zrepl/platformtest/tests.CreateReplicationCursor
+     github.com/zrepl/zrepl/platformtest/tests.GetNonexistent
+     github.com/zrepl/zrepl/platformtest/tests.HoldsWork
+     ...
+     github.com/zrepl/zrepl/platformtest/tests.SendStreamNonEOFReadErrorHandling
+     github.com/zrepl/zrepl/platformtest/tests.UndestroyableSnapshotParsing
+   SKIPPED TESTS:
+     github.com/zrepl/zrepl/platformtest/tests.SendArgsValidationEncryptedSendOfUnencryptedDatasetForbidden__EncryptionSupported_false
+   FAILED TESTS: []
+
+
+If there is a failure, or a skipped test that you believe should be passing, re-run the test suite, capture stderr & stdout to a text file, and create an issue on GitHub.
+
+To run a specific test case, or a subset of tests matched by regex, use the ``-run REGEX`` command line flag.
+
+To stop test execution at the first failing test, and prevent cleanup of the dummy zpool, use the ``-failure.stop-and-keep-pool`` flag.
+
+To build the platformtests yourself, use ``make test-platform-bin``.
+There's also the ``make test-platform`` target to run the platform tests with a default command line.

docs/usage/runbooks/migrating_sending_side_to_new_zpool.rst

@@ -0,0 +1,36 @@
+
+Migrating Sending Side
+~~~~~~~~~~~~~~~~~~~~~~
+
+**Objective**:
+Move sending-side zpool to new hardware.
+Make the move fully transparent to the sending-side jobs.
+After the move is done, all sending-side zrepl jobs should continue to work as if the move had not happened.
+In particular, incremental replication should be able to pick up where it left before the move.
+
+Suppose we want to migrate all data from one zpool ``oldpool`` to another zpool ``newpool``.
+A possible reason might be that we want to change RAID levels, ``ashift``, or just migrate over to next-gen hardware.
+
+If the pool names are different, zrepl's matching between sender and receiver dataset will break becase the receive-side dataset names contain ``oldpool``.
+To avoid this, we will need the name of the new pool to match that of the old pool.
+The following steps will accomplish this:
+
+1. Stop zrepl.
+2. Create the new pool: ``zpool create newpool ...``
+3. Take a snapshot of the old pool so that you have something that you can ``zfs send``.
+   For example, run ``zfs snapshot -r oldpool@migration_oldpool_newpool``.
+4. Send all of the oldpool's datasets to the new pool:
+   ``zfs send -R oldpool@migration_oldpool_newpool | zfs recv -F newpool``
+5. Export the old pool: ``zpool export oldpool``
+6. Export the new pool: ``zpool export newpool``
+7. (Optional) Change the name of the old pool to something that does not conflict with the new pool.
+   We are going to use the name ``oldoldpool`` in this example.
+   Use ``zpool import`` with no arguments to see the pool id.
+   Then ``zpool import <id> oldoldpool && zpool export oldoldpool``.
+8. Import the new pool, while changing the name to match the old pool: ``zpool import newpool oldpool``
+9. Start zrepl again and wake up the relevant jobs.
+10. Use ``zrepl status`` or you monitoring to ensure that replication works.
+    The best test is an end-to-end test where you write some junk data on a sender dataset and wait until a snapshot with that data appears on the receiving side.
+11. Once you are confident that replication is working, you may dispose of the old pool.
+
+Note that, depending on pruning rules, it will not be possible to switch back to the old pool seamlessly, i.e., without a full re-replication.

endpoint/endpoint.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"path"
+	"strings"
 
 	"github.com/kr/pretty"
 	"github.com/pkg/errors"
@@ -14,6 +15,7 @@ import (
 	"github.com/zrepl/zrepl/daemon/logging/trace"
 
 	"github.com/zrepl/zrepl/replication/logic/pdu"
+	"github.com/zrepl/zrepl/util/bandwidthlimit"
 	"github.com/zrepl/zrepl/util/chainedio"
 	"github.com/zrepl/zrepl/util/chainlock"
 	"github.com/zrepl/zrepl/util/envconst"
@@ -34,6 +36,8 @@ type SenderConfig struct {
 	SendCompressed       bool
 	SendEmbeddedData     bool
 	SendSaved            bool
+
+	BandwidthLimit bandwidthlimit.Config
 }
 
 func (c *SenderConfig) Validate() error {
@@ -44,6 +48,9 @@ func (c *SenderConfig) Validate() error {
 	if _, err := StepHoldTag(c.JobID); err != nil {
 		return fmt.Errorf("JobID cannot be used for hold tag: %s", err)
 	}
+	if err := bandwidthlimit.ValidateConfig(c.BandwidthLimit); err != nil {
+		return errors.Wrap(err, "`BandwidthLimit` field invalid")
+	}
 	return nil
 }
 
@@ -54,16 +61,21 @@ type Sender struct {
 	FSFilter zfs.DatasetFilter
 	jobId    JobID
 	config   SenderConfig
+	bwLimit  bandwidthlimit.Wrapper
 }
 
 func NewSender(conf SenderConfig) *Sender {
 	if err := conf.Validate(); err != nil {
 		panic("invalid config" + err.Error())
 	}
+
+	ratelimiter := bandwidthlimit.WrapperFromConfig(conf.BandwidthLimit)
+
 	return &Sender{
 		FSFilter: conf.FSF,
 		jobId:    conf.JobID,
 		config:   conf,
+		bwLimit:  ratelimiter,
 	}
 }
 
@@ -94,15 +106,10 @@ func (s *Sender) ListFilesystems(ctx context.Context, r *pdu.ListFilesystemReq)
 	}
 	rfss := make([]*pdu.Filesystem, len(fss))
 	for i := range fss {
-		encEnabled, err := zfs.ZFSGetEncryptionEnabled(ctx, fss[i].ToString())
-		if err != nil {
-			return nil, errors.Wrap(err, "cannot get filesystem encryption status")
-		}
 		rfss[i] = &pdu.Filesystem{
 			Path: fss[i].ToString(),
 			// ResumeToken does not make sense from Sender
 			IsPlaceholder: false, // sender FSs are never placeholders
-			IsEncrypted:   encEnabled,
 		}
 	}
 	res := &pdu.ListFilesystemRes{Filesystems: rfss}
@@ -148,29 +155,11 @@ func sendArgsFromPDUAndValidateExistsAndGetVersion(ctx context.Context, fs strin
 	return version, nil
 }
 
-func (s *Sender) Send(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, io.ReadCloser, error) {
-	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
+func (s *Sender) sendMakeArgs(ctx context.Context, r *pdu.SendReq) (sendArgs zfs.ZFSSendArgsValidated, _ error) {
 
 	_, err := s.filterCheckFS(r.Filesystem)
 	if err != nil {
-		return nil, nil, err
-	}
-	switch r.Encrypted {
-	case pdu.Tri_DontCare:
-		// use s.encrypt setting
-		// ok, fallthrough outer
-	case pdu.Tri_False:
-		if s.config.Encrypt.B {
-			return nil, nil, errors.New("only encrypted sends allowed (send -w + encryption!= off), but unencrypted send requested")
-		}
-		// fallthrough outer
-	case pdu.Tri_True:
-		if !s.config.Encrypt.B {
-			return nil, nil, errors.New("only unencrypted sends allowed, but encrypted send requested")
-		}
-		// fallthrough outer
-	default:
-		return nil, nil, fmt.Errorf("unknown pdu.Tri variant %q", r.Encrypted)
+		return sendArgs, err
 	}
 
 	sendArgsUnvalidated := zfs.ZFSSendArgsUnvalidated{
@@ -190,30 +179,19 @@ func (s *Sender) Send(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, io.Rea
 		},
 	}
 
-	sendArgs, err := sendArgsUnvalidated.Validate(ctx)
+	sendArgs, err = sendArgsUnvalidated.Validate(ctx)
 	if err != nil {
-		return nil, nil, errors.Wrap(err, "validate send arguments")
+		return sendArgs, errors.Wrap(err, "validate send arguments")
 	}
+	return sendArgs, nil
+}
 
-	si, err := zfs.ZFSSendDry(ctx, sendArgs)
+func (s *Sender) Send(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, io.ReadCloser, error) {
+	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
+
+	sendArgs, err := s.sendMakeArgs(ctx, r)
 	if err != nil {
-		return nil, nil, errors.Wrap(err, "zfs send dry failed")
-	}
-
-	// From now on, assume that sendArgs has been validated by ZFSSendDry
-	// (because validation involves shelling out, it's actually a little expensive)
-
-	var expSize int64 = 0      // protocol says 0 means no estimate
-	if si.SizeEstimate != -1 { // but si returns -1 for no size estimate
-		expSize = si.SizeEstimate
-	}
-	res := &pdu.SendRes{
-		ExpectedSize:    expSize,
-		UsedResumeToken: r.ResumeToken != "",
-	}
-
-	if r.DryRun {
-		return res, nil, nil
+		return nil, nil, err
 	}
 
 	// create holds or bookmarks of `From` and `To` to guarantee one of the following:
@@ -256,6 +234,21 @@ func (s *Sender) Send(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, io.Rea
 	//
 	// Note further that a resuming send, due to the idempotent nature of func CreateReplicationCursor and HoldStep,
 	// will never lose its step holds because we just (idempotently re-)created them above, before attempting the cleanup.
+	destroyTypes := AbstractionTypeSet{
+		AbstractionStepHold:                           true,
+		AbstractionTentativeReplicationCursorBookmark: true,
+	}
+	// The replication planner can also pick an endpoint zfs abstraction as FromVersion.
+	// Keep it, so that the replication will succeed.
+	//
+	// NB: there is no abstraction for snapshots, so, we only need to check bookmarks.
+	if sendArgs.FromVersion != nil && sendArgs.FromVersion.IsBookmark() {
+		dp, err := zfs.NewDatasetPath(sendArgs.FS)
+		if err != nil {
+			panic(err) // sendArgs is validated, this shouldn't happen
+		}
+		liveAbs = append(liveAbs, destroyTypes.ExtractBookmark(dp, sendArgs.FromVersion))
+	}
 	func() {
 		ctx, endSpan := trace.WithSpan(ctx, "cleanup-stale-abstractions")
 		defer endSpan()
@@ -268,48 +261,90 @@ func (s *Sender) Send(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, io.Rea
 			return keep
 		}
 		check := func(obsoleteAbs []Abstraction) {
-			// last line of defense: check that we don't destroy the incremental `from` and `to`
-			// if we did that, we might be about to blow away the last common filesystem version between sender and receiver
-			mustLiveVersions := []zfs.FilesystemVersion{sendArgs.ToVersion}
-			if sendArgs.FromVersion != nil {
-				mustLiveVersions = append(mustLiveVersions, *sendArgs.FromVersion)
+			// Ensure that we don't delete `From` or `To`.
+			// Regardless of whether they are in AbstractionTypeSet or not.
+			// And produce a nice error message in case we do, to aid debugging the resulting panic.
+			//
+			// This is especially important for `From`. We could break incremental replication
+			// if we deleted the last common filesystem version between sender and receiver.
+			type Problem struct {
+				sendArgsWhat string
+				fullpath     string
+				obsoleteAbs  Abstraction
 			}
-			for _, staleVersion := range obsoleteAbs {
-				for _, mustLiveVersion := range mustLiveVersions {
-					isSendArg := zfs.FilesystemVersionEqualIdentity(mustLiveVersion, staleVersion.GetFilesystemVersion())
-					stepHoldBasedGuaranteeStrategy := false
-					k := replicationGuaranteeStrategy.Kind()
-					switch k {
-					case ReplicationGuaranteeKindResumability:
-						stepHoldBasedGuaranteeStrategy = true
-					case ReplicationGuaranteeKindIncremental:
-					case ReplicationGuaranteeKindNone:
-					default:
-						panic(fmt.Sprintf("this is supposed to be an exhaustive match, got %v", k))
-					}
-					isSnapshot := mustLiveVersion.IsSnapshot()
-					if isSendArg && (!isSnapshot || stepHoldBasedGuaranteeStrategy) {
-						panic(fmt.Sprintf("impl error: %q would be destroyed because it is considered stale but it is part of of sendArgs=%s", mustLiveVersion.String(), pretty.Sprint(sendArgs)))
+			problems := make([]Problem, 0)
+			checkFullpaths := make(map[string]string, 2)
+			checkFullpaths["ToVersion"] = sendArgs.ToVersion.FullPath(sendArgs.FS)
+			if sendArgs.FromVersion != nil {
+				checkFullpaths["FromVersion"] = sendArgs.FromVersion.FullPath(sendArgs.FS)
+			}
+			for _, a := range obsoleteAbs {
+				for what, fullpath := range checkFullpaths {
+					if a.GetFullPath() == fullpath && a.GetType().IsSnapshotOrBookmark() {
+						problems = append(problems, Problem{
+							sendArgsWhat: what,
+							fullpath:     fullpath,
+							obsoleteAbs:  a,
+						})
 					}
 				}
 			}
-		}
-		destroyTypes := AbstractionTypeSet{
-			AbstractionStepHold:                           true,
-			AbstractionTentativeReplicationCursorBookmark: true,
+			if len(problems) == 0 {
+				return
+			}
+			var msg strings.Builder
+			fmt.Fprintf(&msg, "cleaning up send stale would destroy send args:\n")
+			fmt.Fprintf(&msg, "  SendArgs: %s\n", pretty.Sprint(sendArgs))
+			for _, check := range problems {
+				fmt.Fprintf(&msg, "would delete %s %s because it was deemed an obsolete abstraction: %s\n",
+					check.sendArgsWhat, check.fullpath, check.obsoleteAbs)
+			}
+			panic(msg.String())
 		}
 		abstractionsCacheSingleton.TryBatchDestroy(ctx, s.jobId, sendArgs.FS, destroyTypes, keep, check)
 	}()
 
-	sendStream, err := zfs.ZFSSend(ctx, sendArgs)
+	var sendStream io.ReadCloser
+	sendStream, err = zfs.ZFSSend(ctx, sendArgs)
 	if err != nil {
 		// it's ok to not destroy the abstractions we just created here, a new send attempt will take care of it
 		return nil, nil, errors.Wrap(err, "zfs send failed")
 	}
 
+	// apply rate limit
+	sendStream = s.bwLimit.WrapReadCloser(sendStream)
+
+	res := &pdu.SendRes{
+		ExpectedSize:    0,
+		UsedResumeToken: r.ResumeToken != "",
+	}
+
 	return res, sendStream, nil
 }
 
+func (s *Sender) SendDry(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, error) {
+	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
+
+	sendArgs, err := s.sendMakeArgs(ctx, r)
+	if err != nil {
+		return nil, err
+	}
+
+	si, err := zfs.ZFSSendDry(ctx, sendArgs)
+	if err != nil {
+		return nil, errors.Wrap(err, "zfs send dry failed")
+	}
+
+	// From now on, assume that sendArgs has been validated by ZFSSendDry
+	// (because validation involves shelling out, it's actually a little expensive)
+
+	res := &pdu.SendRes{
+		ExpectedSize:    si.SizeEstimate,
+		UsedResumeToken: r.ResumeToken != "",
+	}
+	return res, nil
+}
+
 func (p *Sender) SendCompleted(ctx context.Context, r *pdu.SendCompletedReq) (*pdu.SendCompletedRes, error) {
 	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
 
@@ -419,6 +454,7 @@ func (p *Sender) Receive(ctx context.Context, r *pdu.ReceiveReq, _ io.ReadCloser
 
 type FSFilter interface { // FIXME unused
 	Filter(path *zfs.DatasetPath) (pass bool, err error)
+	UserSpecifiedDatasets() zfs.UserSpecifiedDatasetsSet
 }
 
 // FIXME: can we get away without error types here?
@@ -430,7 +466,7 @@ type FSMap interface { // FIXME unused
 }
 
 // NOTE: when adding members to this struct, remember
-//       to add them to `ReceiverConfig.copyIn()`
+// to add them to `ReceiverConfig.copyIn()`
 type ReceiverConfig struct {
 	JobID JobID
 
@@ -439,8 +475,22 @@ type ReceiverConfig struct {
 
 	InheritProperties  []zfsprop.Property
 	OverrideProperties map[zfsprop.Property]string
+
+	BandwidthLimit bandwidthlimit.Config
+
+	PlaceholderEncryption PlaceholderCreationEncryptionProperty
 }
 
+//go:generate enumer -type=PlaceholderCreationEncryptionProperty -transform=kebab -trimprefix=PlaceholderCreationEncryptionProperty
+type PlaceholderCreationEncryptionProperty int
+
+// Note: the constant names, transformed through enumer, are part of the config format!
+const (
+	PlaceholderCreationEncryptionPropertyUnspecified PlaceholderCreationEncryptionProperty = 1 << iota
+	PlaceholderCreationEncryptionPropertyInherit
+	PlaceholderCreationEncryptionPropertyOff
+)
+
 func (c *ReceiverConfig) copyIn() {
 	c.RootWithoutClientComponent = c.RootWithoutClientComponent.Copy()
 
@@ -475,6 +525,15 @@ func (c *ReceiverConfig) Validate() error {
 	if c.RootWithoutClientComponent.Length() <= 0 {
 		return errors.New("RootWithoutClientComponent must not be an empty dataset path")
 	}
+
+	if err := bandwidthlimit.ValidateConfig(c.BandwidthLimit); err != nil {
+		return errors.Wrap(err, "`BandwidthLimit` field invalid")
+	}
+
+	if !c.PlaceholderEncryption.IsAPlaceholderCreationEncryptionProperty() {
+		return errors.Errorf("`PlaceholderEncryption` field is invalid")
+	}
+
 	return nil
 }
 
@@ -484,7 +543,11 @@ type Receiver struct {
 
 	conf ReceiverConfig // validated
 
+	bwLimit bandwidthlimit.Wrapper
+
 	recvParentCreationMtx *chainlock.L
+
+	Test_OverrideClientIdentityFunc func() string // for use by platformtest
 }
 
 func NewReceiver(config ReceiverConfig) *Receiver {
@@ -495,6 +558,7 @@ func NewReceiver(config ReceiverConfig) *Receiver {
 	return &Receiver{
 		conf:                  config,
 		recvParentCreationMtx: chainlock.New(),
+		bwLimit:               bandwidthlimit.WrapperFromConfig(config.BandwidthLimit),
 	}
 }
 
@@ -521,9 +585,15 @@ func (s *Receiver) clientRootFromCtx(ctx context.Context) *zfs.DatasetPath {
 		return s.conf.RootWithoutClientComponent.Copy()
 	}
 
-	clientIdentity, ok := ctx.Value(ClientIdentityKey).(string)
-	if !ok {
-		panic("ClientIdentityKey context value must be set")
+	var clientIdentity string
+	if s.Test_OverrideClientIdentityFunc != nil {
+		clientIdentity = s.Test_OverrideClientIdentityFunc()
+	} else {
+		var ok bool
+		clientIdentity, ok = ctx.Value(ClientIdentityKey).(string) // no shadow
+		if !ok {
+			panic("ClientIdentityKey context value must be set")
+		}
 	}
 
 	clientRoot, err := clientRoot(s.conf.RootWithoutClientComponent, clientIdentity)
@@ -544,6 +614,12 @@ func (f subroot) Filter(p *zfs.DatasetPath) (pass bool, err error) {
 	return p.HasPrefix(f.localRoot) && !p.Equal(f.localRoot), nil
 }
 
+func (f subroot) UserSpecifiedDatasets() zfs.UserSpecifiedDatasetsSet {
+	return zfs.UserSpecifiedDatasetsSet{
+		f.localRoot.ToString(): true,
+	}
+}
+
 func (f subroot) MapToLocal(fs string) (*zfs.DatasetPath, error) {
 	p, err := zfs.NewDatasetPath(fs)
 	if err != nil {
@@ -564,7 +640,8 @@ func (s *Receiver) ListFilesystems(ctx context.Context, req *pdu.ListFilesystemR
 	if rphs, err := zfs.ZFSGetFilesystemPlaceholderState(ctx, s.conf.RootWithoutClientComponent); err != nil {
 		return nil, errors.Wrap(err, "cannot determine whether root_fs exists")
 	} else if !rphs.FSExists {
-		return nil, errors.New("root_fs does not exist")
+		getLogger(ctx).WithField("root_fs", s.conf.RootWithoutClientComponent).Error("root_fs does not exist")
+		return nil, errors.Errorf("root_fs does not exist")
 	}
 
 	root := s.clientRootFromCtx(ctx)
@@ -592,11 +669,6 @@ func (s *Receiver) ListFilesystems(ctx context.Context, req *pdu.ListFilesystemR
 			l.WithError(err).Error("cannot get receive resume token")
 			return nil, err
 		}
-		encEnabled, err := zfs.ZFSGetEncryptionEnabled(ctx, a.ToString())
-		if err != nil {
-			l.WithError(err).Error("cannot get encryption enabled status")
-			return nil, err
-		}
 		l.WithField("receive_resume_token", token).Debug("receive resume token")
 
 		a.TrimPrefix(root)
@@ -605,7 +677,6 @@ func (s *Receiver) ListFilesystems(ctx context.Context, req *pdu.ListFilesystemR
 			Path:          a.ToString(),
 			IsPlaceholder: ph.IsPlaceholder,
 			ResumeToken:   token,
-			IsEncrypted:   encEnabled,
 		}
 		fss = append(fss, fs)
 	}
@@ -668,6 +739,38 @@ func (s *Receiver) Send(ctx context.Context, req *pdu.SendReq) (*pdu.SendRes, io
 	return nil, nil, fmt.Errorf("receiver does not implement Send()")
 }
 
+func (s *Receiver) SendDry(ctx context.Context, r *pdu.SendReq) (*pdu.SendRes, error) {
+	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
+	return nil, fmt.Errorf("receiver does not implement SendDry()")
+}
+
+func (s *Receiver) receive_GetPlaceholderCreationEncryptionValue(client_root, path *zfs.DatasetPath) (zfs.FilesystemPlaceholderCreateEncryptionValue, error) {
+	if !s.conf.PlaceholderEncryption.IsAPlaceholderCreationEncryptionProperty() {
+		panic(s.conf.PlaceholderEncryption)
+	}
+
+	if client_root.Equal(path) && s.conf.PlaceholderEncryption == PlaceholderCreationEncryptionPropertyUnspecified {
+		// If our Receiver is configured to append a client component to s.conf.RootWithoutClientComponent
+		// then that dataset is always going to be a placeholder.
+		// We don't want to burden users with the concept of placeholders if their `filesystems` filter on the sender
+		// doesn't introduce any gaps.
+		// Since the dataset hierarchy up to and including that client component dataset is still fully controlled by us,
+		// using `inherit` is going to make it work in all expected use cases.
+		return zfs.FilesystemPlaceholderCreateEncryptionInherit, nil
+	}
+
+	switch s.conf.PlaceholderEncryption {
+	case PlaceholderCreationEncryptionPropertyUnspecified:
+		return 0, fmt.Errorf("placeholder filesystem encryption handling is unspecified in receiver config")
+	case PlaceholderCreationEncryptionPropertyInherit:
+		return zfs.FilesystemPlaceholderCreateEncryptionInherit, nil
+	case PlaceholderCreationEncryptionPropertyOff:
+		return zfs.FilesystemPlaceholderCreateEncryptionOff, nil
+	default:
+		panic(s.conf.PlaceholderEncryption)
+	}
+}
+
 func (s *Receiver) Receive(ctx context.Context, req *pdu.ReceiveReq, receive io.ReadCloser) (*pdu.ReceiveRes, error) {
 	defer trace.WithSpanFromStackUpdateCtx(&ctx)()
 
@@ -708,15 +811,18 @@ func (s *Receiver) Receive(ctx context.Context, req *pdu.ReceiveReq, receive io.
 			if v.Path.Equal(lp) {
 				return false
 			}
+
+			l := getLogger(ctx).
+				WithField("placeholder_fs", v.Path.ToString()).
+				WithField("receive_fs", lp.ToString())
+
 			ph, err := zfs.ZFSGetFilesystemPlaceholderState(ctx, v.Path)
-			getLogger(ctx).
-				WithField("fs", v.Path.ToString()).
-				WithField("placeholder_state", fmt.Sprintf("%#v", ph)).
+			l.WithField("placeholder_state", fmt.Sprintf("%#v", ph)).
 				WithField("err", fmt.Sprintf("%s", err)).
 				WithField("errType", fmt.Sprintf("%T", err)).
-				Debug("placeholder state for filesystem")
+				Debug("get placeholder state for filesystem")
 			if err != nil {
-				visitErr = err
+				visitErr = errors.Wrapf(err, "cannot get placeholder state of %s", v.Path.ToString())
 				return false
 			}
 
@@ -727,21 +833,34 @@ func (s *Receiver) Receive(ctx context.Context, req *pdu.ReceiveReq, receive io.
 					} else {
 						visitErr = fmt.Errorf("root_fs %q does not exist", s.conf.RootWithoutClientComponent.ToString())
 					}
-					getLogger(ctx).WithError(visitErr).Error("placeholders are only created automatically below root_fs")
+					l.WithError(visitErr).Error("placeholders are only created automatically below root_fs")
 					return false
 				}
-				l := getLogger(ctx).WithField("placeholder_fs", v.Path)
-				l.Debug("create placeholder filesystem")
-				err := zfs.ZFSCreatePlaceholderFilesystem(ctx, v.Path, v.Parent.Path)
+
+				// compute the value lazily so that users who don't rely on
+				// placeholders can use the default value PlaceholderCreationEncryptionPropertyUnspecified
+				placeholderEncryption, err := s.receive_GetPlaceholderCreationEncryptionValue(root, v.Path)
 				if err != nil {
-					l.WithError(err).Error("cannot create placeholder filesystem")
-					visitErr = err
+					l.WithError(err).Error("cannot create placeholder filesystem") // logger already contains path
+					visitErr = errors.Wrapf(err, "cannot create placeholder filesystem %s", v.Path.ToString())
 					return false
 				}
+
+				l := l.WithField("encryption", placeholderEncryption)
+
+				l.Debug("creating placeholder filesystem")
+				err = zfs.ZFSCreatePlaceholderFilesystem(ctx, v.Path, v.Parent.Path, placeholderEncryption)
+				if err != nil {
+					l.WithError(err).Error("cannot create placeholder filesystem") // logger already contains path
+					visitErr = errors.Wrapf(err, "cannot create placeholder filesystem %s", v.Path.ToString())
+					return false
+				}
+				l.Info("created placeholder filesystem")
 				return true
+			} else {
+				l.Debug("filesystem exists")
+				return true // leave this fs as is
 			}
-			getLogger(ctx).WithField("filesystem", v.Path.ToString()).Debug("exists")
-			return true // leave this fs as is
 		})
 	}()
 	getLogger(ctx).WithField("visitErr", visitErr).Debug("complete tree-walk")
@@ -787,6 +906,9 @@ func (s *Receiver) Receive(ctx context.Context, req *pdu.ReceiveReq, receive io.
 		return nil, errors.Wrap(err, "cannot determine whether we can use resumable send & recv")
 	}
 
+	// apply rate limit
+	receive = s.bwLimit.WrapReadCloser(receive)
+
 	var peek bytes.Buffer
 	var MaxPeek = envconst.Int64("ZREPL_ENDPOINT_RECV_PEEK_SIZE", 1<<20)
 	log.WithField("max_peek_bytes", MaxPeek).Info("peeking incoming stream")