Zabbix docker image update monitoring

Monitoring of docker image updates with Zabbix.

Description

Based on “dockcheck” (CLI query to check updates): Github - dockcheck

Shows number of available docker image updates on host (Example: "2 Docker Image updates on host-xyz").
Important: The Docker image version must be specified with :latest (e.g. in a docker-compose file), a fixed version number such as mariadb:10.6 does not work.

Example notification:

Tested with:

• Zabbix Server 7.0.5
• zabbix-agent2 (on Debian 12 server)

Getting Started

Dependencies

• dockcheck.sh
• regclient/regctl (Licensed under Apache-2.0 License)
• Zabbix-Server with timeouts set up to 30 seconds! (Timeout=30)
• Host with zabbix-agent2 and docker installed

Installing

On Zabbix frontend server:

• Download and import the template docker-image-update.yaml
• Assign the Template Docker Image Updates' to the docker host(s) you want to monitor

On all hosts you want to monitor:

Manual:

• Install and configure package zabbix-agent2 (if not installed):

  apt-get install zabbix-agent2  

• download "dockcheck.sh" from dockcheck repository to new directory /etc/zabbix/scripts/ and change permission:

  mkdir /etc/zabbix/scripts
  curl -L https://raw.githubusercontent.com/mag37/dockcheck/main/dockcheck.sh -o /etc/zabbix/scripts/dockcheck.sh
  chown zabbix:zabbix /etc/zabbix/scripts/dockcheck.sh && chmod 0755 /etc/zabbix/scripts/dockcheck.sh

• run "dockcheck.sh" to install regctl:

  bash /etc/zabbix/scripts/dockcheck.sh -n
  # Confirm with "y":   
  Required dependency 'regctl' missing, do you want it downloaded? y/[n] y  
  chown zabbix:zabbix dockcheck.sh && chmod 0755 /etc/zabbix/scripts/regctl

• add "dockcheck.conf" to /etc/zabbix/zabbix_agent2.d/:

  curl -L https://raw.githubusercontent.com/thetorminal/zabbix-docker-image-updates/refs/heads/main/dockcheck.conf -o /etc/zabbix/zabbix_agent2.d/dockcheck.conf

• restart zabbix-agent2

  systemctl restart zabbix-agent2

via Ansible playbook:

• run the playbook zabbix-dockcheck.yml on host(s) you want to monitor docker on.

Version History

• 0.2
  • fixed #2 (dockcheck changed message from "no updates installed" to "no updates available")
  • fixed #2 and #3 (no updates equaled in an error message in zabbix)
• 0.1
  • Initial Release

To-Do

• List name of image, which needs an update (using Zabbix LLD)
  • currently in progress

Acknowledgments

• Github - dockcheck