DRS fails to automatically migrate virtual machines to specific ESXi host.

Products

• VMware vSphere ESXi
• VMware vCenter Server

Issue/Introduction

vSphere Distributed Resource Scheduler (DRS) is not automatically migrating virtual machines to a specific ESXi host within the cluster. Manual vMotion migrations to the affected host complete successfully. Furthermore, placing peer ESXi hosts into maintenance mode does not force virtual machines to migrate to this host via DRS balancing.

Environment

VMware vCenter Server
VMware vSphere ESXi

Cause

The affected ESXi host is excluded from the required VM/Host DRS groups configured within the cluster. Because the host is missing from these mandatory groups, DRS rule constraints prevent it from being evaluated as a valid destination for automatic virtual machine placement.

Resolution

1. Log in to the vSphere Client.

2. Navigate to the cluster containing the affected ESXi host.

3. Select Configure > Configuration > VM/Host Groups.

4. Identify the active Host Groups utilized by the cluster's VM/Host DRS rules.

5. Select the relevant Host Group and click Edit.

6. Add the affected ESXi host to the Host Group members list and click OK.

7. Verify DRS functionality by manually triggering a DRS run or placing a peer host into maintenance mode to simulate cluster balancing.