OSDOCS-4924: Verify max MTU value acceptance

Author: obrown1205

modules/nw-cluster-mtu-change-about.adoc

@@ -35,6 +35,11 @@ When planning your MTU migration there are two related but distinct MTU values t
 
 If your cluster requires different MTU values for different nodes, you must subtract the overhead value for your network plugin from the lowest MTU value that is used by any node in your cluster. For example, if some nodes in your cluster have an MTU of `9001`, and some have an MTU of `1500`, you must set this value to `1400`.
 
+[IMPORTANT]
+====
+To avoid selecting an MTU value that is not acceptable by a node, verify the maximum MTU value (`maxmtu`) that is accepted by the network interface by using the `ip -d link` command.
+====
+
 [id="how-the-migration-process-works_{context}"]
 == How the migration process works