hostRoot was /run/cilium/cgroupv2 with autoMount disabled, but nothing mounts cgroup2 there. The agent mounted one from inside its own private cgroup namespace, so socket-LB attached to the agent's own cgroup and host processes got no Service/LB translation. k3s-prod-1 (Gateway L2 lease holder + kube-vip VIP) therefore could not reach the Gateway VIP, and its apiserver's OIDC authenticator has failed since 2026-09-12. Co-Authored-By: Claude Opus 5.5 <[email protected]>