Merge pull request #39442 from Amrita42/BZ1926013

BZ1926013: added an admonition for subscriptions

Author: lpettyjo

modules/installation-user-infra-generate-k8s-manifest-ignition.adoc

@@ -207,7 +207,12 @@ ifdef::baremetal,baremetal-restricted,ibm-z,ibm-power[]
 +
 [WARNING]
 ====
-If you are installing a three-node cluster, skip the following step to allow the control plane nodes to be schedulable.
+If you are installing a three-node cluster, skip the following step to allow the control plane nodes to be schedulable. This is because control plane nodes then become worker nodes.
+====
++
+[IMPORTANT]
+====
+When you configure control plane nodes from the default unschedulable to schedulable, additional subscriptions are required.
 ====
 endif::baremetal,baremetal-restricted,ibm-z,ibm-power[]
 

modules/nodes-nodes-working-marking.adoc

@@ -6,7 +6,7 @@
 = Understanding how to mark nodes as unschedulable or schedulable
 
 By default, healthy nodes with a `Ready` status are
-marked as schedulable, meaning that new pods are allowed for placement on the
+marked as schedulable, which means that you can place new pods on the
 node. Manually marking a node as unschedulable blocks any new pods from being
 scheduled on the node. Existing pods on the node are not affected.
 

modules/nodes-nodes-working-master-schedulable.adoc

@@ -7,18 +7,23 @@
 
 You can configure control plane nodes to be
 schedulable, meaning that new pods are allowed for placement on the master
-nodes. By default, control plane nodes are not schedulable. 
+nodes. By default, control plane nodes are not schedulable.
 
 You can set the masters to be schedulable, but must retain the worker nodes.
 
 [NOTE]
 ====
-You can deploy {product-title} with no worker nodes on a bare metal cluster. 
+You can deploy {product-title} with no worker nodes on a bare metal cluster.
 In this case, the control plane nodes are marked schedulable by default.
 ====
 
 You can allow or disallow control plane nodes to be schedulable by configuring the `mastersSchedulable` field.
 
+[IMPORTANT]
+====
+When you configure control plane nodes from the default unschedulable to schedulable, additional subscriptions are required. This is because control plane nodes then become worker nodes.
+====
+
 .Procedure
 
 . Edit the `schedulers.config.openshift.io` resource.