[Release-1.29] - LoadBalancers crashing after updating from 1.27.3 to 1.29.3

[brandond]

Backport fix for LoadBalancers crashing after updating from 1.27.3 to 1.29.3

• LoadBalancers crashing after updating from 1.27.3 to 1.29.3 #9949

[fmoral2]

Validated on Version:

-$  k3s version v1.29.5+k3s-485eaf31 (485eaf31)

Environment Details

Infrastructure
Cloud EC2 instance

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

Cluster Configuration:
-1 nodes

Steps to validate the fix

1. start k3s with --node-ip=1pv4,1pv6
2. Patch service traefik to -p '{"spec": {"externalTrafficPolicy": "Local"}}'
3. Validate nodes, pods,serviceLB

Reproduction Issue:

 k3s version v1.30.1+k3s-5cf4d757 (5cf4d757)

 kubectl patch service traefik  -n kube-system -p '{"spec": {"externalTrafficPolicy": "Local"}}'
 service/traefik patched

 kubectl get pod -n kube-system -l svccontroller.k3s.cattle.io/svcname=traefik

NAME                           READY   STATUS             RESTARTS      AGE
svclb-traefik-a436cc37-mwskr   0/2     CrashLoopBackOff   2 (13s ago)   15s



~$ kubectl  get pods -A
NAMESPACE     NAME                                      READY   STATUS             RESTARTS       AGE
kube-system   local-path-provisioner-75bb9ff978-bf7fw   1/1     Running            0              4m59s
kube-system   coredns-576bfc4dc7-h8nlj                  1/1     Running            0              4m59s
kube-system   helm-install-traefik-crd-x84bt            0/1     Completed          0              4m59s
kube-system   helm-install-traefik-4bbh4                0/1     Completed          1              4m59s
kube-system   metrics-server-557ff575fb-sfwzq           1/1     Running            0              4m59s
kube-system   traefik-5fb479b77-8nmm8                   1/1     Running            0              4m32s
kube-system   svclb-traefik-a436cc37-mwskr              0/2     CrashLoopBackOff   10 (12s ago)   2m56s

Validation Results:

 
 
 $  kubectl  get pods -A
NAMESPACE     NAME                                     READY   STATUS      RESTARTS   AGE
kube-system   coredns-6799fbcd5-gx6s2                  1/1     Running     0          2m45s
kube-system   helm-install-traefik-crd-fkbzk           0/1     Completed   0          2m46s
kube-system   helm-install-traefik-xjtgj               0/1     Completed   1          2m46s
kube-system   local-path-provisioner-6f5d79df6-ftm65   1/1     Running     0          2m45s
kube-system   metrics-server-54fd9b65b-c5252           1/1     Running     0          2m45s
kube-system   svclb-traefik-11b98ccc-8fb6x             2/2     Running     0          2m20s
kube-system   traefik-7d5f6474df-pmgqn                 1/1     Running     0          2m20s


ubuntu@ip-:~$ kubectl get pod -n kube-system -l svccontroller.k3s.cattle.io/svcname=traefik
NAME                           READY   STATUS    RESTARTS   AGE
svclb-traefik-11b98ccc-8fb6x   2/2     Running   0          2m26s


ubuntu@ip-:~$ kubectl patch service traefik  -n kube-system -p '{"spec": {"externalTrafficPolicy": "Local"}}'
service/traefik patched


ubuntu@ip-:~$ kubectl get pod -n kube-system -l svccontroller.k3s.cattle.io/svcname=traefik
NAME                           READY   STATUS    RESTARTS   AGE
svclb-traefik-11b98ccc-khckq   2/2     Running   0          5s


ubuntu@ip-:~$ kubectl  get pods -A
NAMESPACE     NAME                                     READY   STATUS      RESTARTS   AGE
kube-system   coredns-6799fbcd5-gx6s2                  1/1     Running     0          3m13s
kube-system   helm-install-traefik-crd-fkbzk           0/1     Completed   0          3m14s
kube-system   helm-install-traefik-xjtgj               0/1     Completed   1          3m14s
kube-system   local-path-provisioner-6f5d79df6-ftm65   1/1     Running     0          3m13s
kube-system   metrics-server-54fd9b65b-c5252           1/1     Running     0          3m13s
kube-system   svclb-traefik-11b98ccc-khckq             2/2     Running     0          14s
kube-system   traefik-7d5f6474df-pmgqn                 1/1     Running     0          2m48s