Docker autoheal

This tool monitors and restarts unhealthy docker containers. This functionality was proposed to be included with the addition of HEALTHCHECK, however didn't go through. This tool is a workaround till there is native support for --restart-on-unhealthy or similar (moby/moby#22719).

Disclaimer

This docker-autoheal is a rewrite of the excellent docker-autoheal from Will Farrell, but in golang. It is fully compliant with willfarrell/docker-autoheal, plus few goodies such as metrics (see below)

Compatibility

• AUTOHEAL_INTERVAL, AUTOHEAL_START_PERIOD, AUTOHEAL_DEFAULT_STOP_TIMEOUT and CURL_TIMEOUT are duration and are treated as seconds if no unit provided. For more precision 5 can be written 5s.
• DOCKER_SOCK env variable can be written to more standard DOCKER_HOST. DOCKER_SOCK can still be used.

Configuration

Environment variable to configure docker-autoheal

Env var name	Default	Description
AUTOHEAL_CONTAINER_LABEL	autoheal	Specify the name of the label optin'ing to autoheal process. A special value all means all containers are watched
AUTOHEAL_INTERVAL	5s	Interval at which containers health is checked
AUTOHEAL_START_PERIOD	0s	Warmup time before running the first check
AUTOHEAL_DEFAULT_STOP_TIMEOUT	10s	Time to give to containers before shutting down
DOCKER_HOST (or DOCKER_SOCK)	/var/run/docker.sock	Path/URI of docker socket
CURL_TIMEOUT	30s	Timeout when interacting with docker

Additional configuration for the containers

Label name	Description
autoheal	if true or AUTOHEAL_CONTAINER_LABEL=all, means this container is watched
autoheal.stop.timeout	Per containers override for stop timeout seconds during restart, as a duration, e.g. 120s

Metrics

Metrics name	Type	Description
check_count	counter	Count how many times containers have been checked
check_failure_count	counter	Count how many failures happened trying to check containers
restart_count	counter	Count how many containers have been restated
restart_failure_count	counter	Count how many restart failures happened