[DOC][CASSANDRA] Default StorageClass for Cassandra deployment

As Cassandra (via k8ssandra-operator) requires either a default
StorageClass, the instructions to set the default in the OOM docs
and removed the hardcoded "storageClass" setting in cassandra
installation.

Issue-ID: OOM-3226

Change-Id: I815614c31ae6b7fcb811d86519d0df1cc4a8898d
Signed-off-by: Andreas Geissler <andreas-geissler@telekom.de>

4 files changed, 18 insertions, 3 deletions

diff --git a/docs/sections/guides/infra_guides/oom_infra_base_config_setup.rst b/docs/sections/guides/infra_guides/oom_infra_base_config_setup.rst
index f27277ddc9..e84f578c01 100644
--- a/docs/sections/guides/infra_guides/oom_infra_base_config_setup.rst
+++ b/docs/sections/guides/infra_guides/oom_infra_base_config_setup.rst
@@ -15,6 +15,7 @@
 .. _Istio setup guide: https://istio.io/latest/docs/setup/install/helm/
 .. _Gateway-API: https://gateway-api.sigs.k8s.io/
 .. _Istio-Gateway: https://istio.io/latest/docs/reference/config/networking/gateway/
+.. _DefaultStorageClass: https://kubernetes.io/docs/tasks/administer-cluster/change-default-storage-class/
 
 .. _oom_base_setup_guide:
 
@@ -116,6 +117,17 @@ Verify the plugins are installed::
     deploy      1.0.0     install (upgrade if release exists) parent chart and all subcharts as separate but related releases
     undeploy    1.0.0     delete parent chart and subcharts that were deployed as separate releases
 
+Set the default StorageClass
+----------------------------
+
+In some ONAP components it is important to have a default storageClass defined (e.g. cassandra),
+if you don't want to explicitly set it during the deployment via helm overrides.
+
+Therefor you should set the default storageClass (if not done during the K8S cluster setup) via the command:
+
+    > kubectl patch storageclass <storageclass> -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
+
+see `DefaultStorageClass`_
 
 Install the Strimzi Kafka Operator
 ----------------------------------
diff --git a/docs/sections/guides/infra_guides/oom_infra_deployment_requirements.rst b/docs/sections/guides/infra_guides/oom_infra_deployment_requirements.rst
index 0d2271026b..e21c4b68c8 100644
--- a/docs/sections/guides/infra_guides/oom_infra_deployment_requirements.rst
+++ b/docs/sections/guides/infra_guides/oom_infra_deployment_requirements.rst
@@ -48,9 +48,9 @@ The versions of software that are supported by OOM are as follows:
   ==============     ===========  =======  ========  ========  =============  ========
   Release            Kubernetes   Helm     kubectl   Docker    Cert-Manager   Strimzi
   ==============     ===========  =======  ========  ========  =============  ========
-  Jakarta            1.22.4       3.6.3    1.22.4    20.10.x   1.8.0          0.28.0
   Kohn               1.23.8       3.8.2    1.23.8    20.10.x   1.8.0          0.32.0
   London             1.23.8       3.8.2    1.23.x    20.10.x   1.12.2         0.35.0
+  Montreal           1.23.8       3.10.2   1.23.x    20.10.x   1.12.2         0.35.0
   ==============     ===========  =======  ========  ========  =============  ========
 
 .. table:: OOM Software Requirements (production)
@@ -59,6 +59,7 @@ The versions of software that are supported by OOM are as follows:
   Release            Istio   Gateway-API  Keycloak
   ==============     ======  ============ ==============
   London             1.17.2  v0.6.2       19.0.3-legacy
+  Montreal           1.17.2  v0.6.2       19.0.3-legacy
   ==============     ======  ============ ==============
 
 .. table:: OOM Software Requirements (optional)
@@ -66,7 +67,7 @@ The versions of software that are supported by OOM are as follows:
   ==============     ================= ==========
   Release            Prometheus Stack  K8ssandra
   ==============     ================= ==========
-  Jakarta            35.x
   Kohn               35.x
   London             45.x              1.6.1
+  Montreal           45.x              1.8.0
   ==============     ================= ==========
diff --git a/kubernetes/common/cassandra/values.yaml b/kubernetes/common/cassandra/values.yaml
index 5bff17eaef..2f24750072 100644
--- a/kubernetes/common/cassandra/values.yaml
+++ b/kubernetes/common/cassandra/values.yaml
@@ -26,7 +26,7 @@ k8ssandraOperator:
   enabled: true
   cassandraVersion: 4.0.1
   persistence:
-    storageClassName: default
+    #storageClassName: default
     size: 10Gi
   config:
     clusterName: cassandra
diff --git a/kubernetes/common/common/templates/_cassOp.tpl b/kubernetes/common/common/templates/_cassOp.tpl
index 6cf9c3ce7e..d6133422a3 100644
--- a/kubernetes/common/common/templates/_cassOp.tpl
+++ b/kubernetes/common/common/templates/_cassOp.tpl
@@ -35,7 +35,9 @@ spec:
     serverVersion: {{ .Values.k8ssandraOperator.cassandraVersion }}
     storageConfig:
       cassandraDataVolumeClaimSpec:
+        {{ if .Values.k8ssandraOperator.persistence.storageClassName -}}
         storageClassName: {{ .Values.k8ssandraOperator.persistence.storageClassName }}
+        {{- end }}
         accessModes:
           - ReadWriteOnce
         resources: