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pilot8
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Block Size and unable to run snapshot -

Hello,

I have the following LUNS carved out for my windows 2008 r2 SQL  box.

ESX 4.0

LUN1 - OS   1MB block size - 230GB size

LUN2 - DataA  4MB block size - 950GB

LUN2 - DataB  4MB block size - 500GB

LUN3 - logs     1MB block size - 200GB

When I try to run a veeam backup,  got the following error

File <unspecified filename> is larger than the maximum size supported by datastore '<unspecified datastore>

what could be the cause and how to fix so I can run a backup on this VM. How large a LUN should I create ?

Joe.

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john23
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john23
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check this KB, would be helpful

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

-A

Thanks -A Read my blogs: www.openwriteup.com
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logiboy123
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When you snapshot a server it will put all snapshot files in the same lun that the .vmx file is located in. If you change the block size of LUN1 to 4mb you will resolve the issue. Typically I prefer to have all disks for a VM on the same LUN if I can. In your particular case it might be worth creating a single 2TB LUN and presenting it with an 8MB block size.

Regards,

Paul

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boss01
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Move the vmx file to 4mb Block size and check..

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pilot8
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Hi,

Thank you for your reply. So when you say,   " move the the vmx file to 4mb Block size" do you mean moving the OS lun disk?  which is where the .vmx file is.  Also does it matter how large the 4MB lun disk is ? I was wondering if this 4 MB lun disk should be enough to hold all the snapshots for all the LUNs.

thanks!

Joe.

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edk
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You're going to need to storage vmotion (or otherwise move the entire  VM) to the LUN with a larger block size. Just keep in mind this LUN will need to hold the deltas for your snapshots. If the VMs are highly transactional these snaps can grow rather large. The space is reclaimed when the snap is consolidated of course.

Also keep in mind, the block size can only be changed at the time of formatting your LUN. Choose the size wisely and think about the growth of any future VMs. For reference, here are the limitations on maximum VMDK size per blocksize:

1MB | 256GB

2MB | 512GB

4MB | 1TB

8MB | 2TB

Hope this helps.

- Ed K | PHD Virtual Support
a_p_
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Rather than moving files (the vmx file alone does not work btw) you can also redirect the snapshots to another datastore with an appropriate block size and sufficient free disk space. Actually you don't want to keep the snapshots for a long time, only as long as it takes to e.g. run a backup. So they usually won't become very large.

André

PS: Forgot to attach the link: http://kb.vmware.com/kb/1002929