Auto-import images into the embedded registry while k3s is running

[r65535]

Is your feature request related to a problem? Please describe.
k3s can load a bunch of resources from disk:

• k8s manifests from /var/lib/rancher/k3s/server/manifests
• Helm chart tgz can be hosted from /var/lib/rancher/k3s/server/static/charts
• k3s required oci images from /var/lib/rancher/k3s/agent/images/k3s-airgap-images-amd64.tar.zst

With the new embedded registry, it'd be nice to also have a directory that can auto-load in miscellaneous OCI images (similar to k3s-airgap-images-amd64.tar.zst, but for arbitrary images). Especially in an edge/airgapped environment.

Describe alternatives you've considered
A crontab that finds files in a local directory and k3s ctr images import each TAR file 😓

[brandond]

The Spegel embedded registry mirror only supports mirroring things that can be loaded into containerd's image store. It has no store of its own. Containerd does not, as far as I know, support storing arbitrary OCI artifacts in its image store.

Feel free to open an issue at https://github.com/XenitAB/spegel and/or https://github.com/containerd/containerd - once they support it, we can too.

[brandond]

Or perhaps I'm misunderstanding what you mean by "miscellaneous" / "arbitrary" OCI images. Are you just asking for periodic re-import of tarballs from the images directory, instead of only importing them on startup?

That's been asked for in the past, but hasn't been prioritized. Homebrewing something with ctr -n k8s.io image import is probably your best bet.

[r65535]

As an example, I want to deploy bitnami/zookeeper to k3s in an airgapped environment.

• I can host the helm tgz in /var/lib/rancher/k3s/server/static/charts
• I can auto-deploy the helm chart using a manifest HelmChart CRD in /var/lib/rancher/k3s/server/manifests

But I can't load the zookeeper.tar containing the container image into the new embedded registry, without manually running k3s ctr images import zookeeper.tar. It'd be great if I could drop in that zookeeper.tar to a directory on the k3s server, and it auto-loads that image into the registry

[brandond]

Thanks for the additional context. I'll leave this on the backlog.

[harsimranmaan]

Autoloading approach can also help with managing image load times by deferring image imports for #9242

[VestigeJ]

Validated in each minor issue #11559 (comment)