Merge branch 'AbhiK_minikube_persistence' into 'master'

Readme changes regarding minikube persistence

See merge request rac-docker-dev/oracle-database-operator!206

Author: yunus-qureshi

config/samples/sidb/oraclerestdataservice.yaml

@@ -54,7 +54,7 @@ spec:
   ## volumeName is optional. Specify for binding to a specific PV and set storageClass to an empty string to disable automatic volume provisioning
   # persistence:
   #  size: 50Gi
-  ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+  ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
   #  storageClass: "oci-bv"
   #  accessMode: "ReadWriteOnce"
   #  volumeName: ""

config/samples/sidb/singleinstancedatabase.yaml

@@ -71,7 +71,7 @@ spec:
   ## volumeName is optional. Specify for binding to a specific PV and set storageClass to an empty string to disable automatic volume provisioning
   persistence:
     size: 100Gi
-    ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+    ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
     storageClass: "oci-bv"
     accessMode: "ReadWriteOnce"
     volumeName: ""

config/samples/sidb/singleinstancedatabase_clone.yaml

@@ -35,7 +35,7 @@ spec:
   ## accessMode can only accept one of ReadWriteOnce, ReadWriteMany
   persistence:
     size: 100Gi
-    ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+    ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
     storageClass: "oci-bv"
     accessMode: "ReadWriteOnce"
 

config/samples/sidb/singleinstancedatabase_create.yaml

@@ -53,7 +53,7 @@ spec:
   ## accessMode can only accept one of ReadWriteOnce, ReadWriteMany
   persistence:
     size: 100Gi
-    ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+    ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
     storageClass: "oci-bv"
     accessMode: "ReadWriteOnce"
 

config/samples/sidb/singleinstancedatabase_express.yaml

@@ -42,7 +42,7 @@ spec:
   ## accessMode can only accept one of ReadWriteOnce, ReadWriteMany
   persistence:
     size: 50Gi
-    ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+    ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
     storageClass: "oci-bv"
     accessMode: "ReadWriteOnce"
 

config/samples/sidb/singleinstancedatabase_patch.yaml

@@ -43,7 +43,7 @@ spec:
   ## accessMode can only accept one of ReadWriteOnce, ReadWriteMany
   persistence:
     size: 100Gi
-    ## oci-bv applies to OCI block volumes. Update as appropriate for other cloud service providers
+    ## oci-bv applies to OCI block volumes. Use "standard" storageClass for dynamic provisioning in Minikube. Update as appropriate for other cloud service providers
     storageClass: "oci-bv"
     accessMode: "ReadWriteOnce"
 

docs/sidb/PREREQUISITES.md

@@ -17,3 +17,11 @@ To deploy Oracle Database Operator for Kubernetes on Oracle Docker images, compl
 
   More info on creating persistent volumes available at [https://kubernetes.io/docs/concepts/storage/persistent-volumes/](https://kubernetes.io/docs/concepts/storage/persistent-volumes/)
 
+* ### Minikube Cluster Environment
+  
+  By default, Minikube creates a node with 2GB RAM, 2 CPUs, and 20GB disk space when a cluster is created using `minikube start` command. However, these resources (particularly disk space and RAM) may not be sufficient for running and managing Oracle Database using the OraOperator. It is recommended to have larger RAM and disk space for better performance. For example, the following command creates a Minikube cluster with 6GB RAM and 50GB disk space for the Minikube VM:
+  
+  ```
+  minikube start --memory=6g --disk-size=50g
+  ```
+

docs/sidb/README.md

@@ -255,12 +255,31 @@ The database persistence can be achieved in the following two ways:
 #### Dynamic Persistence
 In **Dynamic Persistence Provisioning**, a persistent volume is provisioned by mentioning a storage class. For example, **oci-bv** storage class is specified in the **[singleinstancedatabase_create.yaml](../../config/samples/sidb/singleinstancedatabase_create.yaml)** file. This storage class facilitates dynamic provisioning of the OCI block volumes. The supported access mode for this class is `ReadWriteOnce`. For other cloud providers, you can similarly use their dynamic provisioning storage classes.
 
-**Note:** Generally, the `Reclaim Policy` of such dynamically provisioned volumes is `Delete`. These volumes are deleted when their corresponding database deployment is deleted. To retain volumes, use static provisioning, as explained in the Block Volume Static Provisioning section.
+**Note:** 
+- Generally, the `Reclaim Policy` of such dynamically provisioned volumes is `Delete`. These volumes are deleted when their corresponding database deployment is deleted. To retain volumes, use static provisioning, as explained in the Block Volume Static Provisioning section.
+- In **Minikube**, the dynamic persistence provisioning class is **standard**.
 
 #### Static Persistence
 In **Static Persistence Provisioning**, you have to create a volume manually (either using Block Volume or NFS), and then use the name of this volume with the `<.spec.persistence.volumeName>` field (corresponds to the `volumeName` field of the persistence section in the **[singleinstancedatabase.yaml](../../config/samples/sidb/singleinstancedatabase.yaml)**). The `Reclaim Policy` of such volume can be set to `Retain`. So, this volume does not get deleted with the deletion of its corresponding deployment. The access modes supported with block volume and NFS are `ReadWriteOnce` and `ReadWriteMany` respectively. 
+**Note:**
+In **Minikube**, a persistent volume can be provisioned using the sample yaml file below:
+```yaml
+apiVersion: v1
+kind: PersistentVolume
+metadata:
+  name: db-vol
+spec:
+  capacity:
+    storage: 10Gi
+  accessModes:
+    - ReadWriteMany
+  persistentVolumeReclaimPolicy: Retain
+  hostPath:
+    path: <host-path-for-pv>
+```
+Further, the volume name (i.e. db-vol) can be mentioned in the `volumeName` field of the **[singleinstancedatabase.yaml](../../config/samples/sidb/singleinstancedatabase.yaml)**. `storageClass` field is not required in this case, and can be left empty.
 
-Static Persistence Provisioning in OCI is explained in the following subsections:
+Static Persistence Provisioning in Oracle Cloud Infrastructure (OCI) is explained in the following subsections:
 
 ##### Block Volume Static Provisioning
 With block volume static provisioning, you must manually create a block volume resource from the OCI console, and fetch its `OCID`. To create the persistent volume, you can use the following YAML file: