OCPBUGS-57625: Added warning note to br-ex doc for reserved SDN int names

Author: dfitzmau

modules/creating-manifest-file-customized-br-ex-bridge.adoc

@@ -54,6 +54,26 @@ If you require an environment with a single network interface controller (NIC) a
 After you install {op-system-first} and the system reboots, the Machine Config Operator injects Ignition configuration files into each node in your cluster, so that each node received the `br-ex` bridge network configuration. To prevent configuration conflicts, the `configure-ovs.sh` shell script receives a signal to not configure the `br-ex` bridge.
 endif::postinstall-bare-metal-ipi,postinstall-bare-metal-upi[]
 
+[WARNING]
+====
+The following list of interface names are reserved and you cannot use the names with NMstate configurations:
+
+* `br-ext`
+* `br-int`
+* `br-local`
+* `br-nexthop`
+* `br0`
+* `ext-vxlan`
+* `ext`
+* `genev_sys_*`
+* `int`
+* `k8s-*`
+* `ovn-k8s-*`
+* `patch-br-*`
+* `tun0`
+* `vxlan_sys_*`
+====
+
 .Prerequisites
 ifndef::postinstall-bare-metal-ipi,postinstall-bare-metal-upi[]
 * Optional: You have installed the link:https://nmstate.io/[`nmstate`] API so that you can validate the NMState configuration.