Restarting VMware VirtualCenter Server service triggers large Amount of DRS vMotions

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• DRS migrates a large amount of virtual machines after restarting VMware VirtualCenter Server service.
• Environments with large clusters are most likely to experience this issue.

Environment

VMware vCenter Server 6.0.x
VMware vCenter Server 5.5.x

Cause

DRS recommendations are invoked after only 50% of the hosts in a cluster report quickstats data. Quickstats data is cleared after vCenter Service restarts. In larger clusters, DRS recommendations based on 50% of the host data may result in a large fluctuation of VMotions on restart of the vCenter service.

Resolution

This is a known issue affecting VMware vCenter Server 5.5 and 6.0.

Currently, there is no resolution.

To work around this issue, edit and add these entries to vpxd.cfg file on the vCenter Server to:

• Suppress the amount of DRS migration on start up
• Increase the number of ESXi hosts vCenter Server requires to return quickstat data before providing DRS recommendations
  
  Note: Take a backup of C:\ProgramData\VMware\VMware VirtualCenter\vpxd.cfg file before making any changes.
  

<vpxd>
<quickStats>
<HostStatsCheck>true</HostStatsCheck>
</quickStats>
<drmMinQuickStatsPerc>90</drmMinQuickStatsPerc>
</vpxd>

Additional Information

VMware VirtualCenter Server サービスを再起動すると、DRS によって多数の vMotion が実行される