Merge pull request #6 from HCL-TECH-SOFTWARE/sync/cf225_b

Sync/cf225 b

Author: marcvincentvista

docs/deploy_dx/install/kubernetes_deployment/preparation/mandatory_tasks/prepare_persistent_volume_claims.md

@@ -324,3 +324,63 @@ spec:
   volumeMode: Filesystem
 
 ```
+
+## Configuring additional WebEngine persistent volumes
+
+A HCL Digital Experience Compose Kubernetes deployment requires a number of persistent volumes as standard, such as for the WebEngine logs and customizations and for digital asset storage. It is now also possible to connect additional persistent volumes to the DX WebEngine stateful set and mount them in the main container of all WebEngine pods. It is anticipated that this optional feature will be of use to customers running custom applications on DX Compose that require additional persistent storage.
+
+This feature allows you to configure additional Persistent Volume Claims (PVCs) for the WebEngine stateful set and specify the directories at which they will be mounted in the main containers of all WebEngine pods. 
+
+!!! important
+    WebEngine pods will remain "Pending" until all the new claims have been satisfied. Please ensure that you have created the necessary Persistent Volumes in advance or have suitable provisioners in your Kubernetes cluster to create the volumes on demand.
+
+The following syntax can be used to configure additional Persistent Volume Claims (PVCs) in your `custom-values.yaml`:
+
+```yaml
+volumes:
+  # Persistent Volumes for webEngine
+  webEngine:
+    # List of optional additional WebEngine PVCs one per webEngine pod - RWO for customer applications
+    # Each list element must include a unique "name", one or more "accessModes"
+    # Only supported option is ReadWriteOnce, a "mountPath" specifying where in the
+    # WebEngine container it should be mounted, a "storageClassName" and a size in "requests/storage".
+    # It may also optionally include a "selector" section to select specific PVs based on their labels.
+    # It may also optionally include a "volumeName" to select a specific PV.
+    # Example:
+    # customPVCs:
+    #   - name: "test1"
+    #     accessModes:
+    #       - "ReadWriteOnce"
+    #     mountPath: "/opt/openliberty/test1"
+    #     storageClassName: "manual"
+    #     requests:
+    #       storage: "20Gi"
+    #     selector:
+    #       matchLabels:
+    #         label: test
+    #       matchExpressions:
+    #         - key: name
+    #           operator: In
+    #           values:
+    #             - test1
+    #             - test2
+    #     volumeName: "test-pv"
+    customPVCs: []
+```
+
+**Example**
+
+The following example creates a new PVC called `<deployment-name>-web-engine-custom-test1` and mounts it in the main WebEngine pod containers at `/opt/openliberty/test1`. To be satisfied this claim requires a Persistent Volume with access mode `ReadWriteOnce`, storage class `manual` and at least 20Gb capacity. Since `volumeName` and `selector` are not specified, Kubernetes is free to choose any unbound volume that meets the above criteria.
+
+```yaml
+volumes:
+  webEngine:
+    customPVCs:
+      - name: "test1"
+        accessModes:
+          - "ReadWriteOnce"
+        mountPath: "/opt/openliberty/test1"
+        storageClassName: "manual"
+        requests:
+          storage: "20Gi"
+```