vmware 5.1 file is larger than the maximum size supported by datastore

I'm facing a situation when veeam tries to take a snapshot of the vm in order to initiate the backup, it gives me the following message: "File is larger than the maximum size supported by datastore" as I've read on the solutions, there are 3 options, listed below.  I may try to move the snapshot to a different datastore with a bigger block size, does anyone have any experience with this error?

There are 3 ways to remedy this:
If you do not want to back this disk up, you can set the disk that is too large for the datastore to "Independent" on the settings of the VM. Right-click the VM, click Edit Settings, click Change disk to Independent. After that the disk needs to be excluded from the job. This will make it so VMware does not take a snapshot of the disk anymore, as Independent disks are not supported by snapshots.
You may want to move the machine to storage with a bigger block size.
You may want to edit the VMX file, so that snapshots will be created on a different datastore that has a bigger block size. Refer to the knowledge base link below for further details:
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Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Yes, its common.

Your virtual machine disk + size of the snapshot exceeds the block size for the disk.

• 1MB block size – 256GB maximum file size
• 2MB block size – 512GB maximum file size
• 4MB block size – 1024GB maximum file size
• 8MB block size – 2048GB maximum file size

see here to change the snapshot location.

Paul SolovyovskySenior IT AdvisorCommented:
The block size on the datastore the VM is on is more than the max. allowed for the VMDK size.  For instance 1MB block size has limit of 256GB VMDK files, 2MB is 512GB unless your VMDK is close to 2TB

The easiest way to fix this is to move VMs to a different datastore and delete/recreate datastore.

If datastore is VMFS 3.x currently, what you can do upgrade to VMFS 5.x that will upgrade the VMFS from MBR to GPT and will leave the datastore in mixed mode, native VMFS 5.x is recommended though.

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jdffAuthor Commented:
I'm a bit confused with the VMware article, so my datastore is 2.18TB VMFS 5.54, isn't that supposed to support it? As you said GPT? Screenshot attached.
Unfortunately I don't have another datastore big enough to move it so I can fix the primary datastore as recommended by you.
Just out of curiosity, how do I see if a datastore is MBR or GPT, I could not find it anywhere on vmware.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Edit the VM properties, and what does it state is the maximum size for the disk ?

This was not a converted VMFS 3 to VMFS 5 ?
Paul SolovyovskySenior IT AdvisorCommented:
How large is the VM?
jdffAuthor Commented:
The VM has multiple hard disks attached, please see the screenshots attached, could it be the problem?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Actually the problem is, that the maximum size of a virtual machine disk on 5.1 is 2TB-512bytes.

see Page 1, of this document...


ESXi 5.5, see Page 1, 62TB


So, it cannot create a snapshot, because this exceeds the maximum size of disk....

Max size is parent virtual disk + snapshot child disk.

that's it!

That's your issue.

You need to reduce the size of the virtual disk, or upgrade to 5.5.

Part 13: HOW TO: Shrink or Reduce a VMware Virtual Machine Disk (VMDK) using VMware vCenter Converter Standalone v5.5.2
Paul SolovyovskySenior IT AdvisorCommented:
I concur, which is why I asked how large the virtual disk was in the first post and the 2TB limit. Upgrade to 5.5 is probably the easiest solution if you don't have extra capacity
jdffAuthor Commented:
Can I tell vmware 5.1 to store the snapshot on a different datastore in the mean time? I need to perform a full backup of the vm in the mean time and then upgrade to 5.5 as I think it will be the best solution. However I have no backup of the 2tb vm hard disk as of right now, and just so you know, I've tried to copy the 2tb vm drive with the vm set to offline to a usb drive attached to my veeam machine and it would take over 4 days to copy the entire thing, which I can't afford to have the vm offline for that period of time, so I've installed a 1tb iscsi NAS in the mean time so I can move the snapshot file to it and have a full backup in the mean time, will this idea work?

Thanks for all the help.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
I'm afraid not. This is not a datastore issue, this is a design limit issue.

The maximum size of the virtual machine disk is 2TB-512bytes, you have set the virtual machine disk to it's absolute MAX.

The virtual disk cannot be extended beyond this, adding a snapshot would increase the virtual disk beyond it's design limit.
Paul SolovyovskySenior IT AdvisorCommented:
I would perform an OS based backup of the VM before upgrading to 5.5
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
jdffAuthor Commented:
Andrew, will vmware converter work without the need to create a snapshot? Veeam won't work until I can fix this thing, and I really want a backup of this vm before upgrading to vmware 5.5, any suggestions? I saw the backup list, but I guess they are all paid versions and many may require the need of a snapshot, isn't this true?
Paul SolovyovskySenior IT AdvisorCommented:
vmware converter works on the Operating System (think P2V except this is a V2V) and will not create a Vmware snapshot.  We also use this to reduce VMDK size as you can shrink the virtual disk int the process if there a large amount of unused capacity in the volume.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
jdffAuthor Commented:
Hi Andrew,
I have used it before, so I guess I can do it while running the vm and it won't be a problem, I will have to dump on a USB drive since I have nothing else of that size to accommodate it.

Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Windows Share ?
jdffAuthor Commented:
Yes, I guess that will be the best option, it may take days to get it done.
jdffAuthor Commented:
Is there a way to exclude disk2 from veeam backup and perform a backup from the vm + another vm on a different data store?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
You should be able to specify, that in the job options, to be specific about what is selected on the VM.
jdffAuthor Commented:
I'm trying to run the conversion so I can have some sort of backup before upgrading to version 5.5, but I'm getting errors on different options. Can you please try to help. Isn't there a third party backup software that could backup this image in the mean time? Perhaps a software with a trial period, this way it would allow me time to convert to 5.5.

On option 1 you will see error 1 and option 2 error 2.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
The recommended method is to install Converter on the Machine to be converted, and the destination for backup is a Windows Share Name

e.g. \\servername\share

If converter is too much trouble, the only other option which does not involve a snapshot is to follow this EE Article of mine. The VM must be powered off.

Part 10: HOW TO: Backup (Export) and Restore (Import) virtual machines to VMware vSphere Hypervisor 5.1 for FREE
jdffAuthor Commented:
Andrew, doing as you said, I get the following error. I haven't tried the powered off option because backing over 2tb of data may take as long as 3 days which I can't afford to have the machine offline. Any explanation for the error message attached error3?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Yes, Export to OVF, does require the VM to be OFF.

The share \\veeam\image can be written to ?

It's also possible, it's having issues with the size of the disk.

Can you upload the converter logs.
jdffAuthor Commented:
Here it is, I do know that OVF export must be offline , however my concern is with the time involved to copy over 2tb.

Thank you once again for the help.
jdffAuthor Commented:
It worked.
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