Cannot use ipv6 literal as system-default-registry

[brandond]

Environmental Info:
K3s Version: v1.29.3+k3s1

Node(s) CPU architecture, OS, and Version:
n/a

Cluster Configuration:
n/a

Describe the bug:
Cannot use ipv6 literal as system-default-registry

Steps To Reproduce:
start k3s with ipv6 address as system-default-registry, for example:
k3s server --system-default-registry=[fd7c:53a5:aef5::242:ac11:7]

Expected behavior:
works

Actual behavior:
Errors in logs due to image name in pod spec not being quoted:
I0411 08:38:18.324145 54 event.go:376] "Event occurred" object="kube-system/coredns" fieldPath="" kind="Addon" apiVersion="k3s.cattle.io/v1" type="Warning" reason="ParseManifestFailed" message="Parse manifest at \"/var/lib/rancher/k3s/server/manifests/coredns.yaml\" failed: yaml: line 44: did not find expected key"

root@k3s-server-1:/# grep image: /var/lib/rancher/k3s/server/manifests/coredns.yaml
        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-coredns-coredns:1.10.1

The image value should be quoted, otherwise the square brackets are invalid yaml.

Additional context / logs:

• Cannot use IPv6 literal in registry mirror endpoint #9897

[brandond]

I need this for testing IPv6-only clusters, as I don't have external ipv6 connectivity in my environment :/

[aganesh-suse]

Validated on master branch with commit 06b6444

Environment Details

Infrastructure

• Cloud
• Hosted

Node(s) CPU architecture, OS, and Version:

$ cat /etc/os-release
PRETTY_NAME="Ubuntu 22.04.2 LTS"

$ uname -m
x86_64

Cluster Configuration:

HA: 3 server/ 1 agent

Config.yaml:

token: xxxx
cluster-init: true
system-default-registry: "[fd7c:53a5:aef5::242:ac11:7]"
write-kubeconfig-mode: "0644"
node-external-ip: 1.1.1.1
node-label:
- k3s-upgrade=server

Testing Steps

1. Copy config.yaml

$ sudo mkdir -p /etc/rancher/k3s && sudo cp config.yaml /etc/rancher/k3s

2. Install k3s

curl -sfL https://get.k3s.io | sudo INSTALL_K3S_COMMIT='06b6444904294c415b314c78c41cf424e7e749d6' sh -s - server

3. Check the image is with double quotes for ipv6 in all yaml files and that there are no parse manifest errors:

$ sudo journalctl -xeu k3s | grep coredns | grep ParseManifestFailed
$ sudo grep image: /var/lib/rancher/k3s/server/manifests/coredns.yaml
$ sudo grep -rni image: /var/lib/rancher/k3s/server/manifests

Replication Results:

• k3s version used for replication:

$ k3s -v
k3s version v1.29.3+k3s1 (8aecc26b)
go version go1.21.8

 $ sudo journalctl -xeu k3s | grep coredns | grep ParseManifestFailed 
Apr 16 19:34:41 ip-172-31-21-32 k3s[66038]: I0416 19:34:41.361395   66038 event.go:376] "Event occurred" object="kube-system/coredns" fieldPath="" kind="Addon" apiVersion="k3s.cattle.io/v1" type="Warning" reason="ParseManifestFailed" message="Parse manifest at \"/var/lib/rancher/k3s/server/manifests/coredns.yaml\" failed: yaml: line 44: did not find expected key"

 $ sudo grep image: /var/lib/rancher/k3s/server/manifests/coredns.yaml 
        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-coredns-coredns:1.10.1

 $ sudo grep -rni image: /var/lib/rancher/k3s/server/manifests
/var/lib/rancher/k3s/server/manifests/metrics-server/metrics-server-deployment.yaml:47:        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-metrics-server:v0.7.0
/var/lib/rancher/k3s/server/manifests/local-storage.yaml:70:        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/local-path-provisioner:v0.0.26
/var/lib/rancher/k3s/server/manifests/local-storage.yaml:158:        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-library-busybox:1.36.1
/var/lib/rancher/k3s/server/manifests/traefik.yaml:28:    image:
/var/lib/rancher/k3s/server/manifests/coredns.yaml:123:        image: [fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-coredns-coredns:1.10.1

Validation Results:

• k3s version used for validation:

$ k3s -v
k3s version v1.29.3+k3s-06b64449 (06b64449)
go version go1.21.8

$ sudo journalctl -xeu k3s | grep coredns | grep ParseManifestFailed

 $ sudo grep image: /var/lib/rancher/k3s/server/manifests/coredns.yaml
        image: "[fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-coredns-coredns:1.10.1"

 $ sudo grep -rni image: /var/lib/rancher/k3s/server/manifests
/var/lib/rancher/k3s/server/manifests/metrics-server/metrics-server-deployment.yaml:47:        image: "[fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-metrics-server:v0.7.0"
/var/lib/rancher/k3s/server/manifests/local-storage.yaml:70:        image: "[fd7c:53a5:aef5::242:ac11:7]/rancher/local-path-provisioner:v0.0.26"
/var/lib/rancher/k3s/server/manifests/local-storage.yaml:159:        image: "[fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-library-busybox:1.36.1"
/var/lib/rancher/k3s/server/manifests/traefik.yaml:29:    image:
/var/lib/rancher/k3s/server/manifests/coredns.yaml:123:        image: "[fd7c:53a5:aef5::242:ac11:7]/rancher/mirrored-coredns-coredns:1.10.1"