A series of bash/python scripts I wrote to monitor changes in my domains and alert myself.
This script receives the (sub)domain you want to monitor as an argument and monitors for changes to it's SOA record's serial number. If it finds such changes it publishes a message including the previous and current serial number to a specified MQTT topic for notifiers to consume. The dig, mosquitto and mosquitto-clients packages are required to use this script.
Before running the script make sure to set the $MQTT_SRV and $MQTT_TOPIC enviroment variables. To do that run in a terminal:
export $MQTT_SRV=<server-domain-here>
export $MQTT_TOPIC=<mqtt-topic-here>
To run the script periodically, which is it's intended purpose add the following string in your users' crontab and have it run every e.g. 5 minutes.
*/5 * * * * <PATH-TO-SCRIPT>/dnserial.sh <DOMAIN-HERE>