mirror of
https://github.com/docker-mailserver/docker-mailserver.git
synced 2024-01-19 02:48:50 +00:00
4a58e2eb83
- Better clarify images are only updated to newer image updates to the same tag of the running container(s). - Slight revisions to existing content.
54 lines
2.8 KiB
Markdown
54 lines
2.8 KiB
Markdown
---
|
|
title: 'Maintenance | Update and Cleanup'
|
|
---
|
|
|
|
[`containrrr/watchtower`][watchtower-dockerhub] is a service that monitors Docker images for updates, automatically applying them to running containers.
|
|
|
|
!!! example "Automatic image updates + cleanup"
|
|
|
|
Run a `watchtower` container with access to `docker.sock`, enabling the service to manage Docker:
|
|
|
|
```yaml title="compose.yaml"
|
|
services:
|
|
watchtower:
|
|
image: containrrr/watchtower:latest
|
|
# Automatic cleanup (removes older image pulls from wasting disk space):
|
|
environment:
|
|
- WATCHTOWER_CLEANUP=true
|
|
volumes:
|
|
- /var/run/docker.sock:/var/run/docker.sock
|
|
```
|
|
|
|
!!! tip "The image tag used for a container is monitored for updates (eg: `:latest`, `:edge`, `:13`)"
|
|
|
|
The automatic update support is **only for updates to that specific image tag**.
|
|
|
|
- Your container will not update to a new major version tag (_unless using `:latest`_).
|
|
- Omit the minor or patch portion of the semver tag to receive updates for the omitted portion (_eg: `13` will represent the latest minor + patch release of `v13`_).
|
|
|
|
!!! tip "Updating only specific containers"
|
|
|
|
By default the `watchtower` service will check every 24 hours for new image updates to pull, based on currently running containers (_**not restricted** to only those running within your `compose.yaml`_).
|
|
|
|
Images eligible for updates can configured with a [custom `command`][docker-docs-compose-command] that provides a list of container names, or via other supported options (eg: labels). This configuration is detailed in the [`watchtower` docs][watchtower-docs].
|
|
|
|
!!! info "Manual cleanup"
|
|
|
|
`watchtower` also supports running on-demand with `docker run` or `compose.yaml` via the `--run-once` option.
|
|
|
|
You can alternatively invoke cleanup of Docker storage directly with:
|
|
|
|
- [`docker image prune --all`][docker-docs-prune-image]
|
|
- [`docker system prune --all`][docker-docs-prune-system] (_also removes unused containers, networks, build cache_).
|
|
|
|
If you omit the `--all` option, this will instead only remove ["dangling" content][docker-prune-dangling] (_eg: Orphaned images_).
|
|
|
|
[watchtower-dockerhub]: https://hub.docker.com/r/containrrr/watchtower
|
|
[watchtower-cleanup]: https://containrrr.github.io/watchtower/arguments/#cleanup
|
|
[watchtower-docs]: https://containrrr.dev/watchtower/
|
|
|
|
[docker-docs-compose-command]: https://docs.docker.com/compose/compose-file/05-services/#command
|
|
[docker-docs-prune-image]: https://docs.docker.com/engine/reference/commandline/image_prune/
|
|
[docker-docs-prune-system]: https://docs.docker.com/engine/reference/commandline/system_prune/
|
|
[docker-prune-dangling]: https://stackoverflow.com/questions/45142528/what-is-a-dangling-image-and-what-is-an-unused-image/60756668#60756668
|