handson__ocp4_VM_backup_restore.md

OpenShift Virtualization VirtualMachine backup using PV/PVC backup on OCPv4

VirualMachine data is usually stored in the PV/PVC on OCPv4. This testing is for checking if the PV/PVC backup is valid to VM backup too.

Generate some data for checking if the data is remained after backup

$ mkdir /home/fedora/test_dir
$ echo TestData > /home/fedora/test_dir/test.txt

Stop the target VM to backup first.

Create PVC and PV using storageclass dynamically in this test.

$ oc create -f - <<EOF
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: new-backup-pvc
  namespace: backup-test
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 15Gi
  storageClassName: gp2
EOF

Create and run a temporary pod for backup task

$ oc create deployment sleep --image=registry.access.redhat.com/rhel7/rhel-tools -- tail -f /dev/null

Setting up both PVC/PV to the deployment of a temporary pod

$ oc set volume deployment/sleep --add -t pvc --name=old-pvc --claim-name=backup-test-rootdisk-3v2kg --mount-path=/old-pvc
$ oc set volume deployment/sleep --add -t pvc --name=new-pvc --claim-name=new-backup-pvc --mount-path=/new-pvc

Access the pod and backup using "rsync" as follows

$ oc get pvc
NAME                               STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
backup-test-rootdisk-3v2kg         Bound    pvc-c7d8dde6-28a5-4803-aaf8-9b93efab4f9e   15Gi       RWO            gp2            40m
new-backup-pvc                     Bound    pvc-28f99c53-76d3-46e4-8960-6adaa441361a   15Gi       RWO            gp2            2m32s

$ oc get pod
NAME                     READY   STATUS    RESTARTS   AGE
sleep-6f979fcb4d-mvdrz   1/1     Running   0          77s

$ oc rsh sleep-6f979fcb4d-mvdrz

sh-4.2$ ls -al /{old,new}-pvc
/new-pvc:
total 20
drwxrwsr-x. 3 root 1000610000  4096 May 26 06:42 .
drwxr-xr-x. 1 root root          36 May 26 06:42 ..

/old-pvc:
total 1025212
drwxrwsr-x. 2 root 1000610000        4096 May 26 06:03 .
drwxr-xr-x. 1 root root                36 May 26 06:42 ..
-rw-rw----. 1 root 1000610000 15727509504 May 26 06:31 disk.img

sh-4.2$ rsync -avxHAX --progress /old-pvc/* /new-pvc
sending incremental file list
disk.img
 15,727,509,504 100%  157.24MB/s    0:01:35 (xfr#1, to-chk=0/1)

sent 15,731,349,359 bytes  received 35 bytes  163,019,164.70 bytes/sec
total size is 15,727,509,504  speedup is 1.00

Create new VirtualMachine using "existing PVC"

Select with "Existing PVC" after "Create Virtual Machine" -> "New with Wizard"

Add disk with "Using an existing PVC" we created previously

Select the disk as "Boot Source"

And run the new VM.

Verify if the test data is restored

Ok, the data is restored intactly.

Done.