Crater agents

Service configuration

Crater agents are servers with our standard configuration running a Docker container hosting the agent. A timer checks for updates every 5 minutes, and if a newer Docker image is present the container will automatically be updated and restarted. This service is managed with Ansible.

Common maintenance procedures

Starting and stopping the agent

The agent is managed by the container-crater-agent.service systemd unit. That means it’s possible to start, stop and restart it with the usual systemctl commands:

systemctl stop container-crater-agent.service
systemctl start container-crater-agent.service
systemctl restart container-crater-agent.service

Inspecting the logs of the agent

Logs of the agents are forwarded and collected by journald. To see them you can use journalctl:

journalctl -u container-crater-agent.service

Manually updating the container image

The container is updated automatically every 5 minutes (provided a newer image is present). If you need to update them sooner you can manually start the updater service by running this command:

systemctl start docker-images-update.service