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Donzie13
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Thin provisioning not reducing backup sizes

I am using ghettoVCB to back up some of my VMs. I changed some of these VMs to use thin provisioning in an attempt to reduce backup sizes. When I browse my datastore using vSphere Client, I can see that the thin provisioned disks are taking up less space. However, when I back up to an NFS store on a Windows Server 2008 R2 system, the backup sizes are the same as they were when I used thick provisioning. Is this to be expected on a Windows NFS share? I did specify thin provisioning for ghettoVCB.

I ran sdelete and the VMWare Converter to try to shrink the disks; this did decrease disk size I see in the datastore browser but the backup size on the NFS share was still the same.

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lamw
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I don't have access to an NFS server atm, but testing on a ZFS w/de-dupe volume which is exported out as NFS, I can confirm that on the ESX host, the VM shows up as thin-provisioned and when you do ls -lha on the VMDK it's 8GB and not 0GB, but when you look at the datastore free, no space was consumed when this new VM was created. It all depends on your NFS server and it's configuration, I agree with RParker, that you'll want to enable de-dupe on your NFS server if it's supported. Thin provisioned is handled differently on NFS server vs. on VMFS volume and it dictated by the NFS server itself on how it's configured to handle thin provisioning.

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lamw
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Please take a look at FAQ #26 in .

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William Lam

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Twitter: @lamw

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Donzie13
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Hello William!

Thanks for writing ghettoVCB.sh. It's been working great for me.

Yes, I had looked at FAQ #26 and tried to follow its suggestions - that's why I mentioned running sdelete above. I was just wondering if something else might be causing the problem in my case, backing up to Windows NFS. Would you would expect the backed up disk to have the thin size on Windows NFS?

Thanks

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continuum
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AFAIK thin provisioning is a feature of the VMFS filesystem - not a feature of the virtual disk format itself.

Even if you use vmkfstools and export a vmdk with -d thin it will arrive as a regular thick provisioned vmdk on NFS.

If you want to export in a format that does not eat so much space use vmkfstools with -d 2Gbsparse




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VMX-parameters- Workstation FAQ -[ MOA-liveCD|http://sanbarrow.com/moa241.html] - VM-Sickbay


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Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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lamw
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This all depends on your NFS server, there maybe other settings that you may need to look at. If you notice, if you create a VM that resides on NFS, you don't have an option to select "Thin Provisioning", it's generally dictated by the NFS Server, so your YMMV depending on your NFS Server. I don't use Windows NFS, so I can't comment. Would recommend checking Microsoft's KB's to see if there's anything around thin provisioning in general or using another NFS server and see if you get similar results.

=========================================================================

William Lam

VMware vExpert 2009

VMware ESX/ESXi scripts and resources at:

Twitter: @lamw

VMware Code Central - Scripts/Sample code for Developers and Administrators

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If you find this information useful, please award points for "correct" or "helpful".

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continuum
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William

can you confirm that on Linux NFS servers the thin provisioning is maintained ?

Then it would be a issue with Windows NFS-servers only ...




___________________________________

VMX-parameters- Workstation FAQ -[ MOA-liveCD|http://sanbarrow.com/moa241.html] - VM-Sickbay


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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Donzie13
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I don't have a Unix-based NFS handy. I did just run a quick test. I created a VM with an 8GB disk on my Windows NFS and a second VM with an 8GB disk on my VMFS datastore. When I created the VM on the Windows NFS, the 'Allocate and commit space on demand (Thin Provisioning)' option was selected but disabled (grayed out). When I created the VM on the VMFS datastore, I was able to select 'Allocate and commit space on demand (Thin Provisioning)'. The VM on the Windows NFS ended up with an 8GB disk and the VM on the VMFS ended up with a 0GB disk.

So, it does appear to me that Windows NFS does not support thin provisioning.

If you created a VM on Unix NFS would you expect the initial disk size to be 0GB?

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continuum
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If you created a VM on Unix NFS would you expect the initial disk size to be 0GB?

No - I would expect that it is 8 Gb as well - but I may be wrong and hope William can tell us his experiences




___________________________________

VMX-parameters- Workstation FAQ -[ MOA-liveCD|http://sanbarrow.com/moa241.html] - VM-Sickbay


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

RParker
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Moreover I would suggest you use Windows 2008 FILE server as the NFS target. That implements DE-Duplication, which is what you want to save space, NOT thin provision.

You should see big file savings this way.

lamw
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I don't have access to an NFS server atm, but testing on a ZFS w/de-dupe volume which is exported out as NFS, I can confirm that on the ESX host, the VM shows up as thin-provisioned and when you do ls -lha on the VMDK it's 8GB and not 0GB, but when you look at the datastore free, no space was consumed when this new VM was created. It all depends on your NFS server and it's configuration, I agree with RParker, that you'll want to enable de-dupe on your NFS server if it's supported. Thin provisioned is handled differently on NFS server vs. on VMFS volume and it dictated by the NFS server itself on how it's configured to handle thin provisioning.

=========================================================================

William Lam

VMware vExpert 2009

VMware ESX/ESXi scripts and resources at:

Twitter: @lamw

VMware Code Central - Scripts/Sample code for Developers and Administrators

VMware Developer Community

If you find this information useful, please award points for "correct" or "helpful".

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Donzie13
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It sounds to me like Windows Storage Server 2008 deduplication won't be of much help in my situation. The Windows Storage Server uses the Single Instance Storage feature to save space taken up by duplicate files. My backups, which contain large disk image files, won't contain duplicate files.

Am I missing something?

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