Unmount datastore option greyed out

Products

• VMware vSphere ESXi

Issue/Introduction

When trying to unmount or delete the datastore, the option shows greyed out not letting us unmount it.

The datastore unmount button will show as below:

This will not let us decommission/remove the datastore.

 

Environment

VMware vSphere ESXi 7.x

VMware vSphere ESXi 8.x

Cause

• This could happen due to the datastore LUN not presented to the ESXi host anymore.

• That can be verified by searching the LUN identifier on the vCenter under the storage devices of the host:

• Verify the same by using the below commands:

  • esxcli storage vmfs extent list | grep -i <naa.id>

  • partedUtil getptbl /vmfs/devices/disks/naa.id

• The above commands will either return no output or the error 'No such file or directory'.

Resolution

We would need to request the storage vendor to re-present the LUN to the ESXi hosts and then follow the correct procedure the decommission the datastore by first unmounting the datastore, detaching the LUN and then un-presenting it from the backend storage.

The below article has the steps to unmount, detach and remove the datastore:

How to detach a LUN device from ESXi hosts

Additional Information

In case the LUN has been deleted from the backend storage, we will need to remove the entry of the datastore from the vCenter datastore.

Please open a Broadcom support ticket to fix the issue.