Migrate spanned NTFS Volume from 2 1.9TB vmdk to new 3TB vmdk

[wayne7215]

Hi guys

Because of the 2TB vmdk limitation we had until 5.1 we created 2 vmdk disks each with 1.9TB and created a spanned NTFS Volume inside the Win2012 R2 guest. We are now on vSphere 6 update 2 and want to replace this spanned volume with a single new 4TB vmdk. I know it's theoretically a Windows task and we would have to copy the data from the spanned volume to the new disk, but maybe there is somehow an easier way with some VMWare tools? Cool would be to merge the 2 vmdk into 1 vmdk 😉

Any suggestions? Would be nice if we somehow could avoid to restore the whole volume from backup to the new disk.

Thx

[rcporto]

Sorry, but there is no way to merge virtual disks on VMware... You will really to work from the Guest OS side, my recommendation is to use robocopy to sync data from old spanned volume to the new simple volume.

[wayne7215]

And what's about vmware-vdiskmanage? I've seen this blog

How to Merge Multiple VMDK’s into Single VMDK | VIRTUALIZATION BLOG

The point is, if we use a tool like Robocopy on file level, we will lose the dedup space inside the Win2012 R2 OS so the volume would grow from 2.2TB to 3.9TB

I guess we would use to restote the data with a block level tool. We have also Veeam, could Veeam help us somehow?

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[rcporto]

The vmware-vdiskmanage can be used to merge virtual disks that are splitted. Splitted disks can be create for example in solutions like VMware Workstation and Player, where a single 10GB can be splitted in 5 disks of 2GB, instead of a single monolithic disk of 10GB. The reason is just to make the disk easy to move between medias. But your case is different, since your two files are not splitted disk, but two independent disks,

[continuum]

>> The point is, if we use a tool like Robocopy on file level, we will lose the dedup space inside the Win2012 R2 OS so the volume would grow from 2.2TB to 3.9TB
If you use robocopy to copy the contents to a newly created thin provisioned vmdk you will only get a vmdk as large as the actually used space - it will not grow to 3.9TB !
I completely agree with what has already been said here - vmware-vdiskmanager is no help here - and robocopy is the smartest way to do this.

[wayne7215]

If you use robocopy to copy the contents to a newly created thin provisioned vmdk you will only get a vmdk as large as the actually used space - it will not grow to 3.9TB !

Are you sure? As far as I know robocopy or any other file level based copy mechanism will rehydrate all the data, because the Win2012 dedup is on block level.

What makes you say it's not rehydrating? Any link available?

So I'm still looking for a way to copy all the dedup data from one Win2012R2 volume to a new Win2012R2 volume. Any suggestion for a tool on block level?

Thx