This started as a project to prove that you could check for updates without first pulling every new image to compare against, while that’s not why it kept get getting traction my original answer to this question still seems true:
Due to Docker API limitations the latest image will still be pulled from the registry.
And:
Do not pull new images. When this flag is specified, watchtower will not attempt to pull new images from the registry. Instead it will only monitor the local image cache for changes
It’s also a different approach. With dockcheck you’d run it and then make the choice what you’ll update there and then. Selectively choosing exactly what containers to update at the moment. Or have it completely unattended auto update a selection of images.
With the notifications, you can get notified and then have a sitdown and auto-update what you choose.
It’s just different workflows and options.
The upcoming release will also add a new option to backup the image being updated and then autoprune old backups after N days. To allow for easy rollback if a new image breaks.
Thanks for the detailed explanation.
Will try to see how it fits my setup when I get a chance, but I have been wanting to move away from Watchtower as it is no longer maintained.
Good to know there is an alternative, and from what you describe I like your approach. Having to opt-out of updates in Watchtower never really sat right with me- Watchtower clutter is okay in compose files that actually want something to do with Watchtower…
Thank you.
I hope you can find some usefulness in it. You can also do things by compose labels. As well as dynamically at runtime. Either interactively or as arguments.
Not to take away anything from the OP, but there is a fork of Watchtower that is maintained and works a lot better than the OG Watchtower. The original Watchtower would screw up the update fairly regularly. So, if you want to just yolo your updates, that’d be the way to go. If you want a bit more control, DockCheck seems to have that covered. It’s always good to have choices.
This question is usually asked a lot.
This started as a project to prove that you could check for updates without first pulling every new image to compare against, while that’s not why it kept get getting traction my original answer to this question still seems true:
From Watchtower Docs - Arguments
And:
It’s also a different approach. With dockcheck you’d run it and then make the choice what you’ll update there and then. Selectively choosing exactly what containers to update at the moment. Or have it completely unattended auto update a selection of images.
With the notifications, you can get notified and then have a sitdown and auto-update what you choose.
It’s just different workflows and options.
The upcoming release will also add a new option to backup the image being updated and then autoprune old backups after N days. To allow for easy rollback if a new image breaks.
Thanks for the detailed explanation. Will try to see how it fits my setup when I get a chance, but I have been wanting to move away from Watchtower as it is no longer maintained. Good to know there is an alternative, and from what you describe I like your approach. Having to opt-out of updates in Watchtower never really sat right with me- Watchtower clutter is okay in compose files that actually want something to do with Watchtower…
Thank you. I hope you can find some usefulness in it. You can also do things by compose labels. As well as dynamically at runtime. Either interactively or as arguments.
Not to take away anything from the OP, but there is a fork of Watchtower that is maintained and works a lot better than the OG Watchtower. The original Watchtower would screw up the update fairly regularly. So, if you want to just yolo your updates, that’d be the way to go. If you want a bit more control, DockCheck seems to have that covered. It’s always good to have choices.
https://watchtower.devcdn.net/