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Eyad
Enthusiast
Enthusiast

Expand a VMDK file on a Windows OS VM with no downtime?

Is there any tool, command or a 3ed party product that will allow expanding a drive assigned to a Windows OS virtual machine running on ESX server without the need to shutdown the guest OS

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Troy_Clavell
Immortal
Immortal

that would be a nice to have wouldn't it? In order to expand the drive, in my experience, the VM has to be powered down.

Here is a good article on how to expand the disk, if you have any questions.

http://vmprofessional.com/index.php?content=2k3resize

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Eyad
Enthusiast
Enthusiast

Thank you for the article, the issue is as we are trying to implement VMware in production, having to schedule a downtime to expand a drive compared to not needing to do so with physical servers is becoming more of an issue with application owners.

Also this command don't seem to work for large disks, I had an error that disk is too large when I tried to expand a file share from 534gb to 700gb

hopefully someone in vmworld 2008 will offer a product that would help or VMware make this a feature enhancement Smiley Happy

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Troy_Clavell
Immortal
Immortal

i've never had to expand a .vmdk that big. Check you block sizes on the luns and ensure they are alteast at 4MB

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rossb2b
Hot Shot
Hot Shot

The issue with large disks is probably due to block size or the VMFS volume.

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radu_dinut
Enthusiast
Enthusiast

I don't believe that's the issue there, the disk is already larger than 512MB.

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Eyad
Enthusiast
Enthusiast

I've recreated a new LUN and moved the data to it in order to resolve expanding this drive. the new drive is set to 2mb block size. Should I expect any issues expanding this LUN again in the future being a 2MB block size LUN?

I attached a screen shut of the new lun info.

Thank you all for your reply.

Still hoping that a tool will be available to expand drives without powering off guest OS Smiley Happy

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Eyad
Enthusiast
Enthusiast

I've recreated a new LUN and moved the data to it in order to resolve expanding this drive. the new drive is set to 2mb block size. Should I expect any issues expanding this LUN again in the future being a 2MB block size LUN?

Thank you all for your reply. Still hoping that a tool will be available to expand drives without powering off guest OS Smiley Happy

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Eyad
Enthusiast
Enthusiast

I've recreated a new LUN and moved the data to it in order to resolve expanding this drive. the new drive is set to 2mb block size. Should I expect any issues expanding this LUN again in the future being a 2MB block size LUN?

Thank you all for your reply.

Still hoping that a tool will be available to expand drives without powering off guest OS Smiley Happy

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Troy_Clavell
Immortal
Immortal

my advise to you is to add a LUN with 4MB block size. With a 2MB block size you will only be able to allocate no more than 512GB chunks at once.

1MB=256GB

2MB=512GB

4MB=1024GB

8MB= 2048GB

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dwight
Enthusiast
Enthusiast

If you use a logical volume manager such as the windows Logical Disk Manager snap in or the Symantec Volume manager for storage within the Windows VM. You can increase the amount of disk allocated to a Windows VM without downtime. You just add an additional virtual disk to the VM, which under ESX can be done with the VM running. You can then extend the logical volume and filesystem on the fly to add the disk space using the logical volume manager within the VM.






RHCE, VCP

Blog: http://computing.dwighthubbard.info

RHCE, VCP Blog: http://computing.dwighthubbard.info
ewannema
Enthusiast
Enthusiast

To add a little bit more information. You can do this with dynamic disks under Windows with Disk Managment. If dynamic disks are supported for your configuration you can convert the disk and do as Dwight indicates.

http://wannemacher.us
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Eyad
Enthusiast
Enthusiast

How can I expand a vmdk in ESX while the VM is running, vmkfstools -X would require the VM to be powered down, is there another command that can be used?

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Dave_Mishchenko
Immortal
Immortal

No - the VM must be shutdown to use vmkfstools.

Blaishon
Contributor
Contributor

You might try creating a second disk, converting both to dynamic, and then spanning. Don't remember if that needs a restart or not, but I don't think anything else will work as you can't edit the drives in ESX while the VM is running.

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