After expanding a LUN, the VMware vSphere Web Client does not display the correct size of an RDM

Products

• VMware vSphere ESXi

Issue/Introduction

After increasing the size of a LUN referring to a Virtual Machine RDM disk, you notice in the VMware vSphere Web Client:

• The VMware vSphere Web Client does not report the new value for the LUN size
• The Virtual Machine OS reports the correct value for the LUN size
• Performing a Storage Rescan, the LUN size is not updated with the new value

Environment

vSphere ESXi 7.x

vSphere ESXi 8.x

 

Cause

This is expected behavior (= not a fault).

Resolution

Update the Virtual Machine configuration information by following these steps:

 

 

1.)     Reload the Configuration information of the affected Virtual Machine(s) which owns the RDM which was increased in size

Notes:

- If the RDM resides on a SCSI bus set for physical sharing the Virtual Machine will need to be in a powered off state when the reload is performed

- If the RDM belongs to a Clustered VM, perform the reload on the passive Node by powering down the passive Node and then follow the steps outlined below.

 

1.1)   Log in to the ESXi Host where the affected Virtual Machine is registered on via SSH/Putty

1.2)   List the Virtual Machines currently registered to the ESXi Host:

 

vim-cmd vmsvc/getallvms

 

 

1.3)   Make a note of the vm-id listed for the affected Virtual Machine

1.4)   Run the following command to reload the Config by using the vm-id

 

vim-cmd vmsvc/reload 'vm-id'

 

 

1.5) Evaluate whether the VMware vSphere Web Client does now report the new correct size for the expanded LUN. If the issue persists, proceed with Step 2.) 

 

 

2.)     Remove and Re-add the affected Virtual Machine disk (= RDM) by following the steps outlined in 

KB 314350 - Section "Process to correct descriptor file size and VM settings disk size information"

 

 

Additional Information

Please see KB 314350 for more information along with Impact/Risks.