A CIFS globalmount on a TrueNAS SMB share went stale on every k3s node at once, and csi-driver-smb kept bind-mounting the dead handle into every new pod — fixed with noserverino, a real mount-stat liveness probe, and a DaemonSet that force-unmounts stale CIFS globalmounts.
Three unrelated storage failure modes on the same k3s cluster all present as an unresponsive node — Longhorn iSCSI stalls under memory pressure, CIFS mounts entering D-state, and kubelet mis-measuring ephemeral-storage. How to tell them apart before reaching for the power button.
CIFS mounts in Kubernetes have no reliable timeout option on most kernels. Every obvious fix fails. This documents what was tried, what the kernel actually supports, and the sidecar pattern that works.