Can't take snapshot (file is larger than the max size supported)

[bballlal]

So I'm trying to be able to take snapshots on a guest and I get the error: file is larger than the max size supported by datastore. I've already moved the snapshot to it's own datastore but still get the error.

The VM is Thin Provisioned. When I browse the datastore the VMDK is 1.2TB and the provisioned size is 2TB. Does that provisioned size have to be less than 2TB to be able to do snapshots? If so, is VMWare tools the best way to reduce the provisioned size? Or should I do a storage vMotion to a thick datastore that is less than 2TB?

Thank you kindly for any input.

[vmroyale]

Hello and welcome to the communities.

This probably has to do with the block size of the VMFS datastore. Check out http://kb.vmware.com/kb/1003565 for more info.

[bballlal]

The LUN is VMFS-5 so the only block size is 1MB right? Do I need to extend the datastore over another LUN? Remember I already set the snapshot to point to another LUN but I can undo that I guess. Thanks!

[vGuy]

I think you need to review the size of your virtual disk. There is an overhead space required for snapshot creation, please have a look at the below kb for more details:

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=101238...

VMware converter can be used to reduce the virtual disk size.

...hth!

[bballlal]

Thanks, I saw that article once I think in my extensive research and it mentioned to move where the snapshot is located to accomdate space requirements. That didn't work.

In that article I'm seeing where it says, "For ESXi 5.0, this error occurs when any individual flat .vmdk file  exceeds 2,181,972,430,848 bytes. Try to keep the size of the disk below  2,181,972,430,848 bytes for normal snapshot operations." Since my provisioned VMDK size is 2,199,013,376,000 bytes, it looks like that could be my problem. Since it's thin provisioned and my actual VMDK size is 1,386,994,688,000 bytes...does anyone think reducing the provisioned size will fix my snapshot problem? I've read in another thread somewhere someone saying a storage vmotion to thick eager zeroed and then another storage vmotion to thin again would work? Or is it best to do with VMware converter? It's a large SQL database with an OS and a Data drive so it's going to be a PITA. The administrator who set this up obviously didn't know about this size limitation.

Sorry for all the questions, I'm still pretty new to the VMWare world. Your help is really appreciated.

[vGuy]

bballlal wrote:

In that article I'm seeing where it says, "For ESXi 5.0, this error occurs when any individual flat .vmdk file  exceeds 2,181,972,430,848 bytes. Try to keep the size of the disk below  2,181,972,430,848 bytes for normal snapshot operations." Since my provisioned VMDK size is 2,199,013,376,000 bytes, it looks like that could be my problem. Since it's thin provisioned and my actual VMDK size is 1,386,994,688,000 bytes...does anyone think reducing the provisioned size will fix my snapshot problem?

According to the kb, this seems to be your problem. I will suggest to reduce the provisioned size of the virtual disk.

bballlal wrote:

I've read in another thread somewhere someone saying a storage vmotion to thick eager zeroed and then another storage vmotion to thin again would work? Or is it best to do with VMware converter? It's a large SQL database with an OS and a Data drive so it's going to be a PITA. The administrator who set this up obviously didn't know about this size limitation.

SvMotion will not help you in reducing the provisioned space of the virtual disk. VMware Converter is the safe option since it will clone the VM without impacting/modifying the source VM. Although a downtime will be required.

For reference: http://www.techrepublic.com/blog/networking/how-to-shrink-a-vmdk-using-vmware-converter/5362

...hth!