A single MC worker node was unable to mount volumes, causing degradation with etcd pods. The EBS volume was attached to the EC2 but it was not visible from within the OS. The error in the pods' descriptions is similar to the following.

  Warning  FailedMount  50s (x559 over 18h)    kubelet  MountVolume.MountDevice failed for volume "pvc-182a658b-21c8-431e-ba16-40ebeebc65ca" : rpc error: code = Internal desc = Failed to find device path /dev/xvdac. no device path for device "/dev/xvdac" volume "vol-09641618543711dd4" found

Listing mounts does not include the desired volume but shows others that are attached.

cat /proc/mounts | grep nvme | grep pvc
/dev/nvme1n1 /var/lib/kubelet/pods/b44a3c42-6ba3-44e9-8836-c661f0d9e84b/volumes/kubernetes.io~csi/pvc-1997063a-2e07-496a-9568-f23d3c1c228c/mount ext4 rw,seclabel,relatime 0 0
/dev/nvme2n1 /var/lib/kubelet/pods/bf566881-b824-4861-853b-6005c3b65bc4/volumes/kubernetes.io~csi/pvc-216beb07-f6b8-40df-b690-279a39bf6615/mount ext4 rw,seclabel,relatime 0 0
/dev/nvme8n1 /var/lib/kubelet/pods/a03aade2-ede9-48d1-a085-00ff45e3dc36/volumes/kubernetes.io~csi/pvc-162e63b1-056d-4751-be4f-e54c86c4624f/mount ext4 rw,seclabel,relatime 0 0

    4.14.1

    Unknown

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