Add Zabbix postfix monitoring

.env.dist

@@ -1,5 +1,6 @@
 # Used by docker-compose
 DOCKER_PROJECT_NAME=
+ZABBIX_HOST_NAME=
 
 LDAP_LOG_LEVEL=0
 

README.md

@@ -58,3 +58,21 @@ docker exec -it xxxx-crowdsec-1 cscli alerts remove --ip=x.x.x.x
 docker exec -it xxxx-mailserver-1 fail2ban-client banned
 docker exec -it xxxx-crowdsec-1 setup fail2ban unban x.x.x.x
 ```
+
+## Empty queue for an email
+
+```sh
+mailq | tail +2 | awk 'BEGIN { RS = "" } /postmaster@domain.intranet$/ { print $1 }' | tr -d '*!#' | postsuper -d -
+```
+
+## Re-queue emails for an email
+
+```sh
+mailq | tail +2 | awk 'BEGIN { RS = "" } /postmaster@domain.intranet$/ { print $1 }' | tr -d '*!#' | postsuper -r -
+```
+
+## Mails in queue
+
+```sh
+mailq | cut -d ' ' -f 1 | sort | uniq | wc -l
+```

postfix-stats.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+
+set -eu
+
+ME=$(realpath $(dirname $0))
+
+if [ ! -f $ME/.env ]; then
+    echo "Missing env: $ME/.env"
+    exit 1
+fi
+
+# Load up .env
+set -o allexport
+# Source the file
+. $ME/.env
+set +o allexport
+
+CONTAINER_NAME="${DOCKER_PROJECT_NAME}-mailserver-1"
+
+# See: https://serverfault.com/a/577766/336084
+for q in active  bounce  corrupt  defer  deferred  flush  hold  incoming  maildrop; do
+    zabbix_sender -z $ZABBIX_HOST -s $ZABBIX_HOST_NAME -k "email-monitoring.servers.mx" -o "$(printf '{"data":[{"{#MX_HOST}":"%s", "{#QUEUE_NAME}":"%s"}]}' ${OVERRIDE_HOSTNAME} ${q})" 1>/dev/null
+done
+
+# See: https://serverfault.com/a/577766/336084
+for q in active  bounce  corrupt  defer  deferred  flush  hold  incoming  maildrop; do
+    count=$(docker exec $CONTAINER_NAME find /var/spool/postfix/$q ! -type d -print | wc -l)
+
+    if [ ! -z "${1:-}" ]; then
+        echo $q $count
+    fi
+    zabbix_sender -z $ZABBIX_HOST -s $ZABBIX_HOST_NAME -k "email-monitoring.servers.mx.queue[${OVERRIDE_HOSTNAME},$q]" -o "$count" 1>/dev/null
+done