Error: "Storage DRS is unable to move independent disks"

Products

• VMware vCenter Server

Issue/Introduction

• Storage DRS is unable to migrate an independent hard disk to another datastore. 
  • The independent hard disk is not shared.
• In the Faults section (in vCenter, navigate to the Datastore cluster > Monitor > Storage DRS > Faults), the following errors are observed when Storage DRS attempts to execute a recommendation for placement:

Could not balance datastore space usage

Storage DRS is unable to move independent disks

Environment

VMware vSphere 8.x

Cause

VMs with independent disks are supported when using Storage DRS. However, SDRS will only make recommendations for the independent disks initial placement, including relocation or clone placement.

Storage DRS (SDRS) load balancing is disabled for independent disks by default. While SDRS can make migration recommendations for other types of disks, it doesn't make migration recommendations for independent disks unless configured otherwise.

Resolution

Warning: SDRS load balancing cannot be enabled if any shared independent virtual disks are present; migrating shared independent virtual disks is not supported.

 

To allow SDRS to migrate independent disks, follow the steps below:

1. Take a snapshot of the vCenter. If the vCenter is in an ELM configuration, take powered off snapshots of all nodes in ELM
   • See KB: Snapshot Best practices for vCenter Server Virtual Machines
2. Then click on the vCenter object in vCenter inventory > Configure > Advanced Settings > Edit Settings

• • In the Name field add the following entry: 

config.sdrs.disableSDRSonIndependentDisk

     3. Set the value to false

     4. Click Add

     5. Click Save

 

For more information about adding an advanced setting to vCenter, see Configure Advanced Settings