Yellow Bricks » rcli

SVMotion and disk space

Duncan Epping — Wed, 19 Nov 2008 14:31:52 +0000

I received this question a couple of times and there’s no real definitive answer written anywhere…

“Does storage vmotion require additional disk space on the source volume?”

The answer is: Yes it does. Storage VMotion uses the snapshot technology to release the lock on the source disk. This snapshot is placed on the source volume. So in other words, all changes that take place during a Storage VMotion are written to the delta file. This delta file, can and will grow fast.

So keep this in mind if you need to storage vmotion a VM because the VMFS volume is running out of diskspace… it might run out of diskspace sooner than you think.

"SVMotion and disk space" originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)

Storage VMotion Fails With Error Message “Failed to unstun VM after disk reparent”

Duncan Epping — Wed, 13 Feb 2008 13:35:11 +0000

VMware justed added a new KB article about problems with Storage VMotion script:

Storage VMotion can fail for a virtual machine with the error message:

Failed to unstun VM after disk reparent.

The virtual machine is partially migrated and powered off. Generally, the virtual machine cannot be powered on again.

This issue affects:

Virtual machines converted in-place (not deployed or cloned) from template virtual machines with compact disks.

Virtual machines cloned from a virtual machine of the above type (as well as virtual machines cloned from those virtual machines, and so on).

Virtual machines with disks created with the following command: vmkfstools -i -d . ESX Server 3.5 does not support thin-provisioned (or sparse) disks.

Virtual machines created through the SDK with at least one disk created using the RelocateSpec.transform parameter set to sparse. Again, ESX Server 3.5 does not support thin-provisioned disks.

This issue affects the above types of virtual machines because when a disk that is thin-provisioned, or is flat but was cloned from a virtual machine that thin-provisioned disks, is copied to the target datastore as part of Storage VMotion, the disk’s content ID (CID) value is not preserved (although the content of the disk is correctly copied). When the virtual machine attempts to open the disk, it notices the CID is different from what it expects and fails to resume because it believes the disk is corrupted. In reality, the disk is not corrupted, only the CID is incorrect. So not only does the virtual machine end up powered off, but it cannot be powered back on because the CID is still incorrect.

To identify and solve the problem download the scripts attached to the article!

"Storage VMotion Fails With Error Message “Failed to unstun VM after disk reparent”" originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)

Using vmpmotion.pl on Windows RCLI

Duncan Epping — Fri, 11 Jan 2008 12:54:57 +0000

When using vmpmotion.pl on Windows with the RCLI installed you will need to set some extra environment variables before the script will work. First besure that the Perl filetype is correctly setup. There should be a .pl entry:
Open Windows Explorer, Tools, Folder Options, File Types

Next option is to change the environment variable and add the .pl to the pathext variable:
Properties of My Computer, Advanced, Environment Variables, System variables

"Using vmpmotion.pl on Windows RCLI" originally appeared on Yellow-Bricks.com. Follow us on Twitter and Facebook.
Available now: vSphere 5 Clustering Deepdive. (paper | e-book)