[prometheus-node-exporter] Monitor mailq

monitoring.yml

@@ -57,3 +57,8 @@
 - hosts: fyre.adm.crans.org
   roles:
     - ninjabot
+
+# Monitor mailq with a special text exporter
+- hosts: redisdead.adm.crans.org
+  roles:
+    - prometheus-node-exporter-postfix

roles/prometheus-node-exporter-postfix/files/postfix.sh

@@ -0,0 +1,11 @@
+#!/bin/bash
+#
+# Description: Expose metrics from postfix.
+#
+# Author: Alexandre Iooss <erdnaxe@crans.org>
+
+mailq_length="$(/usr/bin/mailq | grep "[^ ]*@crans.org" | wc -l)"
+
+echo '# HELP postfix_mailq_length Pending mails in mailq.'
+echo '# TYPE postfix_mailq_length gauge'
+echo "postfix_mailq_length ${mailq_length}"

roles/prometheus-node-exporter-postfix/files/prometheus-node-exporter-postfix.service

@@ -0,0 +1,6 @@
+[Unit]
+Description=Collect postfix metrics for prometheus-node-exporter
+
+[Service]
+Type=oneshot
+ExecStart=/bin/bash -c "/usr/share/prometheus-node-exporter/postfix.sh | sponge /var/lib/prometheus/node-exporter/postfix.prom"

roles/prometheus-node-exporter-postfix/files/prometheus-node-exporter-postfix.timer

@@ -0,0 +1,9 @@
+[Unit]
+Description=Run postfix metrics collection every 15 minutes
+
+[Timer]
+OnBootSec=0
+OnUnitActiveSec=15min
+
+[Install]
+WantedBy=timers.target

roles/prometheus-node-exporter-postfix/tasks/main.yml

@@ -0,0 +1,25 @@
+---
+# Install Postfix textfile collector, in bullseye you will have postfix exporter
+- name: Install Postfix textfile collector
+  copy:
+    src: "{{ item.src }}"
+    dest: "{{ item.dest }}"
+    owner: root
+    group: root
+    mode: "{{ item.mode }}"
+  loop:
+    - src: postfix.sh
+      dest: /usr/share/prometheus-node-exporter/postfix.sh
+      mode: "0755"
+    - src: prometheus-node-exporter-postfix.service
+      dest: /etc/systemd/system/prometheus-node-exporter-postfix.service
+      mode: "0644"
+    - src: prometheus-node-exporter-postfix.timer
+      dest: /etc/systemd/system/prometheus-node-exporter-postfix.timer
+      mode: "0644"
+
+- name: Activate prometheus-node-exporter-postfix timer
+  systemd:
+    name: prometheus-node-exporter-postfix.timer
+    enabled: true
+    state: started