Considerations for VCSA time synchronization configuration in VCHA environment

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:
You see the following symptom for VCHA failover when you configure external NTP server for VCHA node.

• Unexpected fail back from new active node to new passive node.
• Unexpected repeating VCHA failover.

Environment

VMware vCenter Server 8.0
VMware vCenter Server 7.0.x
VMware vCenter Server Appliance 6.5.x
VMware vCenter Server Appliance 6.7.x

Cause

When passive node becomes active node by failover, new active node starts to perform time sync with enabling management interface. If new active node needs to adjust time backward, then pschealth fails by vmon service and failover occurs again. If new active node needs to adjust time forward, then another failover will not happen.

Resolution

To avoid unexpected VCHA node failover, it is recommended to configure time synchronization mode as "Host".