Node integration flow

Daemonset host mounts

DaemonSet/klustre-csi-node mounts the following host paths:

• /var/lib/kubelet/plugins and /var/lib/kubelet/pods – required for CSI socket registration and mount propagation.
• /dev – ensures device files (if any) are accessible when mounting Lustre.
• /sbin, /usr/sbin, /lib, /lib64 – expose the host’s Lustre client binaries and libraries to the container.

If your kubelet uses custom directories, update pluginDir and registrationDir in the settings ConfigMap.

CSI socket lifecycle

1. The node plugin listens on csiEndpoint (defaults to /var/lib/kubelet/plugins/lustre.csi.klustrefs.io/csi.sock).
2. The node-driver-registrar sidecar registers that socket with kubelet via registrationDir.
3. Kubelet uses the UNIX socket to call NodePublishVolume and NodeUnpublishVolume when pods mount or unmount PVCs.

If the daemonset does not come up or kubelet cannot reach the socket, run:

kubectl describe daemonset klustre-csi-node -n klustre-system
kubectl logs -n klustre-system daemonset/klustre-csi-node -c klustre-csi

PATH and library overrides

The containers inherit PATH and LD_LIBRARY_PATH values that point at the host bind mounts. If your Lustre client lives elsewhere, override:

• nodePlugin.pathEnv
• nodePlugin.ldLibraryPath

via Helm values or by editing the daemonset manifest.

Health signals

• Kubernetes events referencing lustre.csi.klustrefs.io indicate mount/unmount activity.
• kubectl get pods -n klustre-system -o wide should show one pod per labeled node.
• A missing pod usually means the node label is absent or taints/tolerations are mismatched.