NSX Upgrade Pre-Checks show DNS resolving errors for Hosts

Products

• VMware NSX

Issue/Introduction

Pre-checks for NSX upgrade were run and below errors are seen for some hosts in the environment:

Rebooting the host doesn't resolve the issue.

Pre-Check Error:

MP FQDN nsxm1.example.com is not resolvable on host esxihost2.example.com.

Please ensure DNS is configured on host to resolve the MP FQDN.

Environment

VMware NSX 4.1.2

Cause

This can be caused by a DNS firewall rule that may have been disabled before the prechecks on these hosts, causing them to be unable to communicate with DNS.

Resolution

Workaround:

• Verify the status of the DNS firewall rule on the ESXi host, ensuring it is either enabled or disabled. 
• If the DNS firewall is found to be disabled, re-enable the DNS firewall and perform the Pre-Checks once more.

 

If the above Workaround does not resolve the issue, open a case with VMware by Broadcom support for further troubleshooting.