Using Spegel/Embedded Registry Mirror Issue

[pog-charlesinglese]

Has anyone gotten the wildcard "*" entry to function properly when configuring their /etc/rancher/k3s/registries.yaml? Spegel will only advertise images whose registries are explicitly declared.

https://docs.k3s.io/installation/registry-mirror#enabling-registry-mirroring

[brandond]

Your image must have a registry domain, yes. You can't have an image with no registry. docker.io is the implicit default registry if not specified in the image reference.

For example if you say busybox the implicit registry and tag are applied, and you end up with docker.io/library/busybox:latest

This is just how container image references work.

[brandond]

What version are you using?

[pog-charlesinglese]

What version are you using?

I last attempted it on v1.35.0+k3s1, but also tried on v1.34.3+k3s1.

[pog-charlesinglese]

I have one image in my embedded registry that doesn't follow the recommended naming scheme (e.g. doesn't have a dash or dot prior to the slash). I'm going to try removing it to see if that is the source of the problem. I'd be curious as to why Spegel doesn't advertise any of the images if just one doesn't adhere to the rules.

[pog-charlesinglese]

I've confirmed that it is indeed not behaving when I use the "*" wildcard in the registries.yaml file. All imported images adhere to the proper naming scheme (dots and slashes).

k3s --version

k3s version v1.35.0+k3s1 (a6c6cd15)
go version go1.25.5

cat /etc/rancher/k3s/registries.yaml

mirrors:
  "*":

kubectl get --server https://<KUBE_API_IP>:6443 --raw /metrics | grep spegel

# HELP spegel_mirror_last_success_timestamp_seconds The timestamp of the last successful mirror request.
# TYPE spegel_mirror_last_success_timestamp_seconds gauge
spegel_mirror_last_success_timestamp_seconds 0

---

cat /etc/rancher/k3s/registries.yaml

mirrors:
  "docker.io":
  "quay.io":

kubectl get --server https://<KUBE_API_IP>:6443 --raw /metrics | grep spegel

# HELP spegel_advertised_image_digests Number of image digests advertised to be available.
# TYPE spegel_advertised_image_digests gauge
spegel_advertised_image_digests{registry="docker.io"} 16
spegel_advertised_image_digests{registry="quay.io"} 5
# HELP spegel_advertised_image_tags Number of image tags advertised to be available.
# TYPE spegel_advertised_image_tags gauge
spegel_advertised_image_tags{registry="docker.io"} 8
spegel_advertised_image_tags{registry="quay.io"} 5
# HELP spegel_advertised_images Number of images advertised to be available.
# TYPE spegel_advertised_images gauge
spegel_advertised_images{registry="docker.io"} 16
spegel_advertised_images{registry="quay.io"} 5
# HELP spegel_advertised_keys Number of keys advertised to be available.
# TYPE spegel_advertised_keys gauge
spegel_advertised_keys{registry="docker.io"} 75
spegel_advertised_keys{registry="quay.io"} 5
# HELP spegel_mirror_last_success_timestamp_seconds The timestamp of the last successful mirror request.
# TYPE spegel_mirror_last_success_timestamp_seconds gauge
spegel_mirror_last_success_timestamp_seconds 0

[brandond]

See also

• Wildcard in embedded registry configuration appears to not work rancher/rke2#9553