Online Extend Virtual RDM stored with VM

[Erik_V]

We have a VM running Windows 2003 with one Virtual RDM disk (Stored with VM) for the data partition. The LUN is 100GB and we want to extend this to 150GB.

First we resized the LUN with Command View EVA, than did a rescan on our ESX HBA's. The new size was detected by our ESX servers.

Windows Disk Manager unfortunately does not see the new size of the disk or the new free diskspace, also not after rescan disks.

Also the following command did not work (while the VM was still running):

vmkfstools -X 50g <path to RDM vmdk>

The above command results in the following error message:

Failed to extend disk: device or resource busy.

When running the above command while the VM was not running results in the following error message:

Failed to extend disk: The file specified is not a virtual disk.

When you don't start the above command and just reboot the VM after resizing the LUN with Command View EVA and rescan the HBA's of the ESX servers, the new free space is available and can be used to extend the partition/volume with diskpart.

Is there any way to extend the Windows partition/volume without rebooting?

Regards,

Erik

[vmroyale]

Hello and welcome to the forums.

You just need to use diskpart to extend the volume in Windows now:

At a command prompt:

cd C:\windows\system32

diskpart

At the DISKPART prompt:

list vol

select vol

extend

exit

Good Luck!

[Erik_V]

Thank you for your answer.

That's right and that will work.

But this is only possible after the reboot of the VM.

We don't want to reboot the server for extending the disk.

When you use a Physical RDM then it is possible to extend without rebooting the VM.

But we are using a Virtual RDM, because when then can make snapshot's of the RDM.

[kjb007]

Is the RDM your system disk, or a secondary data disk?

-KjB

[Erik_V]

The RDM is a secondary data disk.

[kjb007]

As you've found, since you're not using a vmdk, vmkfstools will not allow you to extend. Since you're using a virtual mode RDM, then your SCSI commands have to go through ESX, and don't come directly from the vm. Have you tried to go into disk manager, and removing the drive letter from the disk. Then perform a rescan?

-KjB

[Erik_V]

I just tried that. Remove driveletter, Rescan Disks but no new space available in Disk Management..

[kjb007]

Since the metadata file is not changed, and can not be changed manually without shutting down the vm, this does not appear to be possible live.

-KjB