Virtual Hard Disk 2TB Limit

We are using Storage Craft to backup a Server 2008 64bit machine.  It has a 10TB direct attached storage as 1 partition.  We are concerned that if we have to virtualize the machine, that their is a 2TB limit on Hyper-V and VMware virtual drives.  

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bgoeringConnect With a Mentor Commented:
Do you need all 10 TB in one volume? It is correct that virtual disk size cannot exceed 2TB-512 bytes for any single vmdk . I haven't tried it, but expect that limit would apply even if you create the vmdk on NFS. If anyone can find documentation to the contrary I would like to see it. The biggest difference with NFS is that the datastore itself can exceed 2TB.

It is also not a supported configuration to attach larger than 2TB LUNs via rdm to a virtual machine - this could sometime work on ESX 3.5 but not on 4.x.

You can, however, present lots of 2TB LUNs and create 2TB - 512 byte vmdks on them. You can also combine them into up to 32 extents to create 64TB datastores. But still have the single file size limit problem.

Now from within the OS you can use dynamic disks and concantination from within the Windows OS to present the appearance of a larger disk to your application.

All that probably isn't a lot of help if you are relying on internal or locally attached storage.

What kind of storage are you using?
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
Correct VMware disk size maxiumum is 2TB - 512 bytes.

You could experiment with Disk Spanning with Dynamic disks.

or you could try VMDirectPath to attach to the storage directly in the guest.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
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If you copied your 10 TB volume to an iSCSI or FC SAN you can connect to it via iSCSI or FC natively from the guest. I connect via iSCSI volumes ranging from w GB to about 600 GB using iSCSI on Windows 2003/2008 VMs running under Hyper-V with no problems. A nice thing about putting the data on native SAN volumes is that you can connect to it from anything, be it physical or virtual. If I decided to move my file server to a physical machine I could just dismount the SAN volumes from my VM and remount them to a new server. The process is much faster than what is possible by copying the files to new storage which would probably take you days.

So, in your situation a SAN is your friend and would give you lots of options for using physical or virtual servers.
Paul SolovyovskySenior IT AdvisorCommented:
If you configure NFS for vmware datastore you can go above the 2TB limit.  I would not virtualize a backup server, defeats the purpose of virtualization, I would keep it physical
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