# This DaemonSet is only active when the cluster is deployed with Multus enabled or EnableCSIHostNetwork
# is set to false. Hopefully in the future it will be part of every Ceph-CSI deployment. Its role is to
# "hold" the Ceph Filesystem mounts that are created by the CSI driver. Essentially, it exposes its
# network namespace into the Kubelet plugin directly and Ceph-CSI picks it up. When mounting, the Ceph-CSI
# driver will use the network namespace of the DaemonSet instead of its own (the plugin pod). This pod
# is not expected to be updated nor restarted unless the node reboots.
kind: DaemonSet
apiVersion: apps/v1
metadata:
  name: csi-cephfsplugin-holder
  namespace: {{ .Namespace }}
spec:
  selector:
    matchLabels:
      app: csi-cephfsplugin-holder
  updateStrategy:
    # DO NOT CHANGE THE STRATEGY
    # The pod is not supposed to be restarted on updates, it should never receive updates too.
    # If it does then the connectivity to the Ceph cluster will be lost and the client I/O will
    # fail.
    type: OnDelete
  template:
    metadata:
      labels:
        app: csi-cephfsplugin-holder
        {{ range $key, $value := .CSICephFSPodLabels }}
        {{ $key }}: "{{ $value }}"
        {{ end }}
    spec:
      # HostPID is needed to expose the correct process ID network namespace and not the process namespace
      hostPID: true
      serviceAccountName: rook-csi-cephfs-plugin-sa
      {{ if .PluginPriorityClassName }}
      priorityClassName: {{ .PluginPriorityClassName }}
      {{ end }}
      containers:
        - name: csi-cephfsplugin-holder
          # This is necessary for the Bidirectional mount propagation
          securityContext:
            privileged: true
          image: {{ .CSIPluginImage }}
          command:
            - "/bin/sh"
            - "-c"
          # the third $ allows the "$$" to be interpreted so it can return the current bash process ID
          args:
            - "ln
              --force
              --symbolic
              --verbose
              /proc/$$$/ns/net
              {{ .KubeletDirPath }}/plugins/$ROOK_CEPH_CSI_DRIVER_NAME/$CEPH_CLUSTER_NAMESPACE.net.ns
              &&
              sleep
              infinity"
          volumeMounts:
            - name: plugin-mount-dir
              mountPath: "{{ .KubeletDirPath }}/plugins"
              mountPropagation: "Bidirectional"
      volumes:
        - name: plugin-mount-dir
          hostPath:
            path: "{{ .KubeletDirPath }}/plugins"
            type: Directory