Impact of changing NTP and DNS server settings on vCenters in Enhanced Linked Mode

Products

• VMware vCenter Server

Issue/Introduction

Administrators may need to update the assigned NTP or DNS server settings for a variety of reasons. Below are some common scenarios:

• Migrating to a new NTP/DNS infrastructure
• Decommissioning legacy DNS or time servers
• Troubleshooting time synchronization or name resolution issues

This article aims to address any concerns about changing NTP or DNS server settings between linked vCenters.

 

Resolution

There is no impact to Enhanced Linked Mode (ELM) vCenters when changing the assigned NTP or DNS server settings. Each vCenter's NTP/DNS settings is configured independently of one another. As long as the new NTP and DNS servers are reachable, there will be no impact. Ensure to monitor and validate the settings after making changes.

Additional Information

You must configure forward and reverse lookup records for the new vCenter hostname before the DNS cutover.

If the cutover is performed without these records, the only remedy is to rebuild the vCenter. Manually changing the FQDN/hostname afterward will not resolve the issue because the underlying registry retains the old FQDN.