Merge pull request #80201 from dfitzmau/OCPBUGS-37415

OCPBUGS-37415: Added a note to the Troubleshooting node network confi…

Author: skopacz1

modules/k8s-nmstate-troubleshooting-dns-disconnected-env.adoc

@@ -8,6 +8,11 @@
 
 If you experience DNS connectivity issues when configuring `nmstate` in a disconnected environment, you can configure the DNS server to resolve the list of name servers for the domain `root-servers.net`.
 
+[IMPORTANT]
+====
+Ensure that the DNS server includes a name server (NS) entry for the `root-servers.net` zone. The DNS server does not need to forward a query to an upstream resolver, but the server must return a correct answer for the NS query.
+====
+
 == Configuring the bind9 DNS named server  
 
 For a cluster configured to query a `bind9` DNS server, you can add the `root-servers.net` zone to a configuration file that contains at least one NS record.