docker-containers: add missing kubelet dependency for container systemd services #78313
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DavHau
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If I understand well, you would like to load Docker image in order to use them with the docker-containers module. There is currently nothing to do this and it seems to me all images used by docker-containers have to be fetched from an Docker registry.
In this context, I'm not in favor of adding a dependency to the kubelet service, just to load Docker images.
Instead, I think you could add a seedDockerImage option in the docker-container module and add some code to load this Docker image in the ExecStartPre script of the container systemd service (something similar to the kubelet module).
If you need to load Docker images for testing purpose, you could use the dockerPreloader module to speed up your tests since it avoids the Docker load at runtime.
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Good points. I was not aware that loading docker images is so trivial that it can be done in a one liner and has nothing to do with kubelet at all. Since So after this we would have:
With having this, we could also remove What do you think? |
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Why would you like to load all images in one go? Also, I think it would be easier to add a |
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Take a look at #78366 ;) |
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You can always mess with I'm neutral on the changes proposed here, but they seem unnecessary. |
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Amazing! #78366 is exactly what i was looking for. This can be closed. Thanks! |
Motivation for this change
Currently docker container systemd services generated by the option
config.docker-containerscan crash on startup when kubelet is not seeding docker images fast enough.I found zero documentation on how to preload docker images via nixos config. But from reading #49379 I guess the right way to do it in production is by using
services.kubernetes.kubelet.seedDockerImages.Therefore the systemd services of
config.docker-containersshould probably depend on kubelet and wait for it to start.Things done
Extend systemd service in
virtualisation/docker-containers.nixto depend also onkubelet.servicein case kubelet is activated viaconfig.services.kubernetes.kubelet.enablesandboxinnix.confon non-NixOS linux)nix-shell -p nixpkgs-review --run "nixpkgs-review wip"./result/bin/)nix path-info -Sbefore and after)