Creating the Engineering Lifecycle Management backup persistent volume and persistent volume claim in the Red Hat® OpenShift®

Engineering Lifecycle Management on Hybrid Cloud requires a persistent volume and persistent volume claim before you create the Engineering Lifecycle Management instance. The backup persistent volume is used to store the backup files of Engineering Lifecycle Management applications configurations. You can use the backup files to restore the application configurations. You can create different types of PVs. For more information, see Types of PVs.

About this task

You must create the persistent volume claim with the predefined name elm-backup-pvc.

Important: The storage capacity of the persistent volume depends on your backup strategy. If you want to keep X number of Engineering Lifecycle Management conf backup files stored in your backup PV, the capacity of the PV should be X*PVC size that is recommended in Engineering Lifecycle Management instance deployment sizes as per your deployment size.

Procedure

To create the persistent volume and persistent volume claim, see Persistent volumes and Persistent volume claims.

Create a persistent volume by creating a YAML file named PV.yaml with the following definition.
```
apiVersion: v1
kind: PersistentVolume
metadata:
  name: elm-backup-pv
spec:
  capacity:
    storage: 100Gi
  accessModes:
    - ReadWriteMany
  nfs:
    server: xx.xx.xx.xx
    path: /data/elmnfs
  persistentVolumeReclaimPolicy: Retain
  storageClassName: <your-storage-class-name>
```
Where:

accessModes

The accessModes defines two characteristics such as read/write capability (ReadWrite or ReadOnly) and access to the volume (Once or Many). You must set the access mode as ReadWriteMany. The persistent volume is shared between the Engineering Lifecycle Management application pods.

nfs

Specified parameters that apply to the selected type. The example that is given is for the NFS type. You must change according to the documentation of the type that you select.

server

NFS server hostname

path

The path that is exported by the NFS server. You must populate the field according to the NFS server.

persistentVolumeReclaimPolicy

The retain policy of persistent volume. You can use Retain to provide reusability.

storageClassName

The type of storage class that persistent volume must use. You must populate the field according to the cluster configuration.

For more information, see Template and sample YAML of PersistentVolume
Create a persistent volume claim, by creating a YAML file named PVC.yaml with the following definition.
```
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: elm-backup-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 10Gi
  volumeName: elm-backup-pv
  storageClassName: rook-cephfs
```
Where:

name

Enter the name as elm-backup-pvc.
Important: You must provide the name as elm-backup-pvc to create the Engineering Lifecycle Management instance.

namespace

Project name where Engineering Lifecycle Management instance is created.

accessModes

The accessModes defines two characteristics such as read/write capability (ReadWrite or ReadOnly) and access to the volume (Once or Many). You must set the access mode as ReadWriteMany.

storage

The storage size that the claim requests for persistent volume. You must populate the field according to the cluster configuration.

volumeName

You must populate the name that is provided during persistent volume creation.

storageClassName

The type of storage class that persistent volume claim must use. You must populate the field according to the cluster configuration.
For more information, see Template and sample YAML of PersistentVolumeClaim
Create the persistent volume by using the following command.
```
oc create -f PV.yaml
```
Create the persistent volume claim by using the following command.
```
oc create -f PVC.yaml
```