Test OpenEBS Local PV by using GKE Local SSD as raw block devices.

gistfile1.txt

(a) Create v1.12.8-gke.10 cluster with one node, two local SSDs. 
(b) Prior to installing openebs, I logged into the node and did the following to wipeout the ext4 that get pre-formatted. 

> sudo umount /mnt/disks/ssd0
> sudo umount /mnt/disks/ssd1
> sudo wipefs -af /dev/sdb
> sudo wipefs -af /dev/sdc
> lsblk -o NAME,TYPE,SIZE,FSTYPE,MOUNTPOINT
NAME    TYPE  SIZE FSTYPE MOUNTPOINT
sda     disk  100G        
├─sda1  part 99.9G ext4   /
├─sda14 part    4M        
└─sda15 part  106M vfat   /boot/efi
sdb     disk  375G        
sdc     disk  375G        

(c) Install openebs using `kubectl apply -f https://openebs.github.io/charts/openebs-operator.yaml`
(d) Run a sample busybox pod with localpv with device type.  `kubectl apply -f busybox-localpv-device.yaml`
(e) Wait for the pod to come to running state. 

```
kubectl get pv -o yaml pvc-34652370-9e19-11e9-9960-42010a800055
apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    local.openebs.io/blockdeviceclaim: bdc-pvc-34652370-9e19-11e9-9960-42010a800055
    pv.kubernetes.io/provisioned-by: openebs.io/local
  creationTimestamp: 2019-07-04T05:04:35Z
  finalizers:
  - kubernetes.io/pv-protection
  labels:
    openebs.io/cas-type: local-device
  name: pvc-34652370-9e19-11e9-9960-42010a800055
  resourceVersion: "4269"
  selfLink: /api/v1/persistentvolumes/pvc-34652370-9e19-11e9-9960-42010a800055
  uid: 376a9b15-9e19-11e9-9960-42010a800055
spec:
  accessModes:
  - ReadWriteOnce
  capacity:
    storage: 5G
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: demo-vol1-claim
    namespace: default
    resourceVersion: "4240"
    uid: 34652370-9e19-11e9-9960-42010a800055
  local:
    fsType: ""
    path: /dev/disk/by-id/scsi-0Google_EphemeralDisk_local-ssd-1
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - gke-kmova-helm-default-pool-f5bbba44-3vg7
  persistentVolumeReclaimPolicy: Delete
  storageClassName: openebs-device
status:
  phase: Bound
```

(f) Login to node and check mount points
```
kiran_mova@gke-kmova-helm-default-pool-f5bbba44-3vg7:~$ sudo mount | grep local
/dev/sdc on /var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/pods/8b8b97a1-9e18-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/pods/8b8b97a1-9e18-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/pods/8b8b97a1-9e18-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/pods/8b8b97a1-9e18-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-8b9057d9-9e18-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
```

(g) Delete the pod and pvc. `kubectl delete -f busybox-localpv-device.yaml`

(h) Login to node and check the mount points - the above command returned empty. All mounts were cleared. 

(i) Recreate the sample busybox pod with localpv with device type.  `kubectl apply -f busybox-localpv-device.yaml`

(j) Wait for the pod to come to running state. Login to node to check for mounts. 

```
sudo mount | grep local
/dev/sdc on /var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/plugins/kubernetes.io/local-volume/mounts/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/pods/3460e826-9e19-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /var/lib/kubelet/pods/3460e826-9e19-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/pods/3460e826-9e19-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
/dev/sdc on /home/kubernetes/containerized_mounter/rootfs/var/lib/kubelet/pods/3460e826-9e19-11e9-9960-42010a800055/volumes/kubernetes.io~local-volume/pvc-34652370-9e19-11e9-9960-42010a800055 type ext4 (rw,relatime,data=ordered)
```