To remove old tagged images that are more than a month old:
$ docker images --no-trunc --format '{{.ID}} {{.CreatedSince}}' \
| grep ' months' | awk '{ print $1 }' \
| xargs --no-run-if-empty docker rmi
Note that it'll fail to remove images that are used by a container, referenced in a repository, has dependent child images... which is probably what you want. Else just add -f
flag.
Example of /etc/cron.daily/docker-gc
script:
#!/bin/sh -e
# Delete all stopped containers (including data-only containers).
docker ps -a -q --no-trunc --filter "status=exited" | xargs --no-run-if-empty docker rm -v
# Delete all tagged images more than a month old
# (will fail to remove images still used).
docker images --no-trunc --format '{{.ID}} {{.CreatedSince}}' | grep ' months' | awk '{ print $1 }' | xargs --no-run-if-empty docker rmi || true
# Delete all 'untagged/dangling' (<none>) images
# Those are used for Docker caching mechanism.
docker images -q --no-trunc --filter dangling=true | xargs --no-run-if-empty docker rmi
# Delete all dangling volumes.
docker volume ls -qf dangling=true | xargs --no-run-if-empty docker volume rm