Unable to vmotion vcls vms to other hosts preventing host maintenance mode task completion

Products

• VMware vCenter Server

Issue/Introduction

Symptoms

• Unable to put the host into maintenance mode as the vCLS VMs fail to migrate.

• Attempting to manually migrate the vCLS VM to another host results in compatibility issues.

• Clicking “More Details” during the migration attempt shows that the virtual machine files are not accessible.

•  Upon further investigation, it is found that the datastore where the vCLS VM resides is marked as inaccessible.

• Attempting to enable Retreat Mode on the cluster (following the steps from “Disable vCLS on a Cluster via Retreat Mode”) fails to clear the vCLS VMs because the underlying datastore is not accessible 

Environment

VMware vCenter Server 7.x

VMware vCenter Server 8.x

Cause

The vCLS VMs cannot be migrated because the datastore volume where the vCLS VMs reside is unmapped from all ESXi hosts directly from the storage side for a maintenance activity. As a result, the virtual machine files became inaccessible, preventing vMotion and causing the maintenance mode task to stall.

Resolution

• Reboot the affected ESXi host. During the reboot, the vCLS VM entries will be automatically removed, as the datastore is no longer mapped to the host.

OR

 • Restore access to the underlying datastore and manually migrate the vCLS VMs to another accessible datastore.