Installing or upgrading to vCenter Server 6.5 fails on the Windows server that uses 53/TCP port (DNS Service)

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Installing or upgrading to VMware vCenter Server 6.5 fails on the Windows server that uses 53/TCP port (DNS Service).
• VMware vCenter Server 6.5 uses 53/TCP port (DNS Service) by default. If this port is in use already, the ports conflicts prevent the following steps from performing: 
  • Fresh installation of VMware vCenter Server 6.5 
  • Upgrade to VMware vCenter Server 6.5

Environment

VMware vCenter Server 6.5.x
VMware vSphere ESXi 6.5

Resolution

To resolve the issue, avoid Installing  VMware vCenter Server 6.5  on the server where DNS server is installed.

Install vCenter Server  6.5 on different server from  DNS server.

Additional Information

Because VMware vCenter Server 6.0 and earlier don't use 53/TCP port, they can be installed on the same DNS server.
Please check if they use the 53/TCP port when upgrading to VMware vCenter Server 6.5. For more information about required ports for VMware vCenter Server 6.5, see the "vSphere Installation and Setup".