Adds additional step to changing the cluster MTU before moving to verification

Author: Steven Smith

modules/nw-cluster-mtu-change.adoc

@@ -345,6 +345,15 @@ where:
 `<mtu>`:: Specifies the new cluster network MTU that you specified with `<overlay_to>`.
 --
 
+. After finalizing the MTU migration, each MCP node is rebooted one by one. You must wait until all the nodes are updated. Check the machine config pool status by entering the following command:
++
+[source,terminal]
+----
+$ oc get mcp
+----
++
+A successfully updated node has the following status: `UPDATED=true`, `UPDATING=false`, `DEGRADED=false`.
+
 .Verification
 
 ifdef::localzone[]