[rhacs-docs-4.6] [RHACS][Docs] ROX-30089: Document Operator Subscription Config for Infra Nodes

cloud_service/installing_cloud_ocp/cloud-install-operator.adoc

@@ -11,6 +11,8 @@ Install the {product-title-short} Operator on your secured clusters.
 
 include::modules/install-acs-operator-cloud.adoc[leveloffset=+1]
 
+include::modules/configuring-the-rhacs-operator-for-infrastructure-nodes.adoc[leveloffset=+2]
+
 [id="next-steps_cloud-install-operator"]
 == Next steps
 

installing/installing_ocp/install-central-ocp.adoc

@@ -23,6 +23,8 @@ You can install Central on your {ocp} or Kubernetes cluster by using one of the
 
 include::modules/install-acs-operator.adoc[leveloffset=+2]
 
+include::modules/configuring-the-rhacs-operator-for-infrastructure-nodes.adoc[leveloffset=+3]
+
 include::modules/install-central-operator.adoc[leveloffset=+2]
 
 [role="_additional-resources"]

modules/configuring-the-rhacs-operator-for-infrastructure-nodes.adoc

@@ -0,0 +1,47 @@
+// Module included in the following assemblies:
+//
+// * installing/installing_ocp/install-central-ocp.adoc
+// * cloud_service/installing_cloud_ocp/cloud-install-operator.adoc
+
+:_mod-docs-content-type: PROCEDURE
+[id="configuring-the-rhacs-operator-for-infrastructure-nodes_{context}"]
+= Configuring the {product-title-short} Operator for infrastructure nodes
+
+To deploy the {rh-rhacs-first} Operator on infrastructure nodes, you can modify its subscription YAML to include `nodeSelector` and `tolerations` to ensure that its pods are scheduled correctly.
+
+.Procedure
+
+. Configure the {product-title-short} Operator with the necessary `nodeSelector` and `tolerations` for infrastructure nodes before you apply the {olm-first} subscription by using the following content, for example:
++
+[source,yaml]
+----
+apiVersion: operators.coreos.com/v1alpha1
+kind: Subscription
+metadata:
+  labels:
+    operators.coreos.com/rhacs-operator.rhacs-operator: ""
+  name: rhacs-operator
+  namespace: rhacs-operator
+spec:
+  channel: stable
+  config:
+    nodeSelector:
+      node-role.kubernetes.io/infra: "" # <1>
+    tolerations:
+      - effect: NoSchedule
+        key: node-role.kubernetes.io/infra # <2>
+        operator: Exists
+  installPlanApproval: Automatic
+  name: rhacs-operator
+  source: redhat-operators
+  sourceNamespace: openshift-marketplace
+----
++
+--
+<1> The `nodeSelector` key and value instruct the Kubernetes scheduler to place the Operator pods on nodes that have the label `node-role.kubernetes.io/infra: ""`.
+<2> The `tolerations` entry allows the Operator pods to be scheduled on nodes that have a taint with the `node-role.kubernetes.io/infra` key. This is necessary as infrastructure nodes are usually provided with a taint to prevent non-infrastructure workloads from being scheduled on them.
+--
+
+. Save the YAML file and apply it by using the OpenShift CLI (`oc`).
+
+When you apply the YAML file, you update the subscription for the {product-title-short} Operator. This in turn configures where the {product-title-short} Operator pods can be scheduled. The `rhacs-operator` namespace is the designated location for the {product-title-short} Operator.

modules/install-acs-operator-cloud.adoc

@@ -1,6 +1,7 @@
 // Module included in the following assemblies:
 //
-// * installing/installing_cloud_ocp/cloud-install-operator.adoc
+// * cloud_service/installing_cloud_ocp/cloud-install-operator.adoc
+
 :_mod-docs-content-type: PROCEDURE
 [id="install-acs-operator-cloud_{context}"]
 = Installing the {product-title-short} Operator for {product-title-managed-short}

modules/install-acs-operator.adoc

@@ -1,6 +1,7 @@
 // Module included in the following assemblies:
 //
-// * installing/install-ocp-operator.adoc
+// * installing/installing_ocp/install-central-ocp.adoc
+
 :_mod-docs-content-type: PROCEDURE
 [id="install-acs-operator_{context}"]
 = Installing the {product-title} Operator
@@ -41,5 +42,4 @@ If you choose manual updates, you must update the {product-title-short} Operator
 .Verification
 * After the installation completes, go to *Operators* -> *Installed Operators* to verify that the {product-title} Operator is listed with the status of *Succeeded*.
 
-.Next Step
-* You installed the Operator into the *rhacs-operator* project. Using that Operator, install, configure, and deploy the `Central` custom resource into the `stackrox` project.
+After you install the Operator into the *rhacs-operator* project, you can install, configure, and deploy the `Central` custom resource (CR) into the `stackrox` project by using the installed Operator.