Merge pull request #69684 from ahardin-rh/understanding-CNO-audit

[OSDOCS-8650]: Content review of Understanding the Cluster Network Operator topic

Author: ahardin-rh

modules/nw-operator-cr.adoc

@@ -42,7 +42,7 @@ endif::[]
 
 The configuration for the cluster network is specified as part of the Cluster Network Operator (CNO) configuration and stored in a custom resource (CR) object that is named `cluster`. The CR specifies the fields for the `Network` API in the `operator.openshift.io` API group.
 
-The CNO configuration inherits the following fields during cluster installation from the `Network` API in the `Network.config.openshift.io` API group and these fields cannot be changed:
+The CNO configuration inherits the following fields during cluster installation from the `Network` API in the `Network.config.openshift.io` API group:
 
 `clusterNetwork`:: IP address pools from which pod IP addresses are allocated.
 `serviceNetwork`:: IP address pool for services.
@@ -52,7 +52,7 @@ The CNO configuration inherits the following fields during cluster installation
 ifdef::post-install-network-configuration,operator[]
 [NOTE]
 ====
-After cluster installation, you cannot modify the fields listed in the previous section.
+After cluster installation, you can only modify the `clusterNetwork` IP address range. The default network type can only be changed from OpenShift SDN to OVN-Kubernetes through migration.
 ====
 endif::[]
 ifndef::post-install-network-configuration[]
@@ -87,13 +87,6 @@ spec:
     hostPrefix: 23
 ----
 
-ifdef::operator[]
-This value is ready-only and inherited from the `Network.config.openshift.io` object named `cluster` during cluster installation.
-endif::operator[]
-ifndef::operator[]
-You can customize this field only in the `install-config.yaml` file before you create the manifests. The value is read-only in the manifest file.
-endif::operator[]
-
 |`spec.serviceNetwork`
 |`array`
 |A block of IP addresses for services. The OpenShift SDN and OVN-Kubernetes network plugins support only a single IP address block for the service network. For example:
@@ -137,7 +130,7 @@ The values for the `defaultNetwork` object are defined in the following table:
 
 |`type`
 |`string`
-|Either `OpenShiftSDN` or `OVNKubernetes`. The {openshift-networking} network plugin is selected during installation. This value cannot be changed after cluster installation.
+|Either `OpenShiftSDN` or `OVNKubernetes`. The {openshift-networking} network plugin is selected during installation. You can change this value by migrating from OpenShift SDN to OVN-Kubernetes. 
 [NOTE]
 ====
 {product-title} uses the OVN-Kubernetes network plugin by default.
@@ -208,13 +201,6 @@ endif::operator[]
 
 |====
 
-ifdef::operator[]
-[NOTE]
-====
-You can only change the configuration for your cluster network plugin during cluster installation.
-====
-endif::operator[]
-
 .Example OpenShift SDN configuration
 [source,yaml]
 ----
@@ -352,12 +338,6 @@ If you set this field to `true`, you do not receive the performance benefits of
 
 |====
 
-ifdef::operator[]
-[NOTE]
-====
-You can only change the configuration for your cluster network plugin during cluster installation, except for the `gatewayConfig` field that can be changed at runtime as a postinstallation activity.
-====
-endif::operator[]
 
 .Example OVN-Kubernetes configuration with IPSec enabled
 [source,yaml]
@@ -372,7 +352,7 @@ defaultNetwork:
 
 [discrete]
 [id="nw-operator-cr-kubeproxyconfig_{context}"]
-=== kubeProxyConfig object configuration
+=== kubeProxyConfig object configuration (OpenShiftSDN container network interface only)
 
 The values for the `kubeProxyConfig` object are defined in the following table:
 
@@ -419,24 +399,15 @@ kind: Network
 metadata:
   name: cluster
 spec:
-  clusterNetwork: <1>
+  clusterNetwork: 
   - cidr: 10.128.0.0/14
     hostPrefix: 23
-  serviceNetwork: <1>
+  serviceNetwork: 
   - 172.30.0.0/16
-  defaultNetwork: <1>
-    type: OpenShiftSDN
-    openshiftSDNConfig:
-      mode: NetworkPolicy
-      mtu: 1450
-      vxlanPort: 4789
-  kubeProxyConfig:
-    iptablesSyncPeriod: 30s
-    proxyArguments:
-      iptables-min-sync-period:
-      - 0s
+  networkType: OVNKubernetes 
+      clusterNetworkMTU: 8900
+    
 ----
-<1> Configured only during cluster installation.
 endif::operator[]
 endif::post-install-network-configuration[]
 

networking/cluster-network-operator.adoc

@@ -23,3 +23,5 @@ include::modules/nw-operator-cr.adoc[leveloffset=+1]
 == Additional resources
 
 * xref:../rest_api/operator_apis/network-operator-openshift-io-v1.adoc#network-operator-openshift-io-v1[`Network` API in the `operator.openshift.io` API group]
+* xref:../networking/configuring-cluster-network-range.adoc#nw-cluster-network-range-edit_configuring-cluster-network-range[Modifying the `clusterNetwork` IP address range]
+* xref:../networking/ovn_kubernetes_network_provider/migrate-from-openshift-sdn.adoc#migrate-from-openshift-sdn[Migrating from the OpenShift SDN network plugin]