docs: apt repo: use sudo in the snippet that sets up the repo

I generally like when snippets are provided in a way which could be used without running as root, and uses sudo when applicable. This change allows for this.

It will, however print out one extra line, which is possible to remove by adding '>/dev/null' after '/etc/apt/sources.list.d/zrepl.list'.

closes #461

config/config_global_test.go

@@ -70,9 +70,9 @@ func TestPrometheusMonitoring(t *testing.T) {
 global:
   monitoring:
     - type: prometheus
-      listen: ':9091'
+      listen: ':9811'
 `)
-	assert.Equal(t, ":9091", conf.Global.Monitoring[0].Ret.(*PrometheusMonitoring).Listen)
+	assert.Equal(t, ":9811", conf.Global.Monitoring[0].Ret.(*PrometheusMonitoring).Listen)
 }
 
 func TestSyslogLoggingOutletFacility(t *testing.T) {

docs/configuration/monitoring.rst

@@ -13,7 +13,7 @@ Prometheus & Grafana
 --------------------
 
 zrepl can expose `Prometheus metrics <https://prometheus.io/docs/instrumenting/exposition_formats/>`_ via HTTP.
-The ``listen`` attribute is a `net.Listen <https://golang.org/pkg/net/#Listen>`_  string for tcp, e.g. ``:9091`` or ``127.0.0.1:9091``.
+The ``listen`` attribute is a `net.Listen <https://golang.org/pkg/net/#Listen>`_  string for tcp, e.g. ``:9811`` or ``127.0.0.1:9811`` (port 9811 was reserved to zrepl `on the official list <https://github.com/prometheus/prometheus/wiki/Default-port-allocations/_compare/43e495dd251ee328ac0d08b58084665b5c0f7a7e...459195059b55b414193ebeb80c5ba463d2606951>`_).
 The ``listen_freebind`` attribute is :ref:`explained here <listen-freebind-explanation>`.
 The Prometheus monitoring job appears in the ``zrepl control`` job list and may be specified **at most once**.
 
@@ -30,7 +30,7 @@ The dashboard also contains some advice on which metrics are important to monito
     global:
       monitoring:
         - type: prometheus
-          listen: ':9091'
+          listen: ':9811'
           listen_freebind: true # optional, default false
 
 

docs/installation/apt-repos.rst

@@ -13,13 +13,13 @@ The following snippet configure the repository for your Debian or Ubuntu release
 
 ::
 
-    apt update && apt install curl gnupg lsb-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: $CODENAME"; \
-    (curl https://zrepl.cschwarz.com/apt/apt-key.asc | apt-key add -) && \
-    (echo "deb [arch=$ARCH] https://zrepl.cschwarz.com/apt/$CODENAME main" > /etc/apt/sources.list.d/zrepl.list) && \
-    apt update
+    (curl https://zrepl.cschwarz.com/apt/apt-key.asc | sudo apt-key add -) && \
+    (echo "deb [arch=$ARCH] https://zrepl.cschwarz.com/apt/$CODENAME main" | sudo tee /etc/apt/sources.list.d/zrepl.list) && \
+    sudo apt update
 
 
 .. NOTE::