vCenter Services Starting Slowly and Unable to Log In

Products

• VMware vCenter Server

Issue/Introduction

• Unable to log into vCenter with [email protected] or AD account.
• Login screen shows spinning wheel after credentials are entered.
• If services are restarted they take much longer than usual to start.

Environment

vCenter Server 8

Cause

vCenter is unable to connect to DNS server. 

To confirm you can check the DNS connection with VDT: 

Using the VCF Diagnostic Tool for vSphere (VDT)

Resolution

Update the DNS server configuration:

Update DNS Server IP address for vCenter Server