Removing unmounted V1 disk groups after upgrading to vSAN 7.0 Update 1 fails

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Removing unmounted V1 disk groups after upgrading to vSAN 7.0 Update 1 fails.
• You see this error similar to:
  
  Unable to remove device: Failed to decommission disk mpx.vmhba1:C0:T1:L0: VsanSysinfoException: Node (5015) ; Status(bad0001)= Failure; Message= Module: plog Instance(0): Input(3) 3 mpx.vmhba1:C0:T4:L0 mpx.vmhba1:C0:T1:L0

Environment

VMware vSphere ESXi 7.0.0

Cause

On-disk format version 1 is no longer supported as of version 7.0U1

Resolution

Upgrade the on-disk format version to the latest version supported by the vSAN version currently in use prior to upgrading to version 7.0U1.

Workaround:
If you already upgraded to version 7.0U1 and the disk groups are unmounted and all data is currently unavailable roll back the upgrade to the previous version of ESXi by following KB Reverting to a previous version of ESXi 6.x, 7.x, and 8.0 (1033604)

If the data is no longer needed on the disk groups follow the below steps.
 

1. Select the host where the disk groups are unmounted.
2. Navigate to Configure and click Storage Devices.
3. Select the disks where partitions need to be erased and click Erase Partitions.
4. Click Refresh.
5. Create new disk group(s) as required.

Additional Information

For additional information, see V1 disk supportability with vSAN 7.0 Update 1 (76436).

Impact/Risks:
Any disk groups still on version 1 will not be mounted in vSAN