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WDShellyFlag for United States of America

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does Veeam backup only used space inside a virtual machine?

I've searched this forum and not found an answer to this question. I've deleted about 300GB of old files from within a Windows 2012 virtual machine running on an ESXi 6 host. If I run a VeeamZip will it only backup the portion of the VM that has files in it or will it backup the space previously occupied by the deleted data?

I believe that vSphere/ESXi will not show the available space as increasing after I do this delete until a certain process is followed (I think running the Mark Russinovich sdelete utility inside the VM and then shutting down the VM and running vmkfstools to reclaim the space in ESXi is required to fully reclaim the space in ESXi). Since Veeam has data compression built in, I wonder if it will backup only the space occupied by files inside the VM? I really don't want to follow all the steps to recover the space in ESXi and have to take the VM down if I don't have to - I'm hoping Veeam doesn't care whether ESXi sees the freed up space or not and is smart enough to backup just the used space inside the VM.

In case you are wondering, I have never run a VeeamZip on this VM and I don't really want to run 2 VeeamZips (before and after the delete) just so I can compare the size of the VeeamZip to answer this question.

Thanks in advance for any help offered.
Avatar of David Johnson, CD
David Johnson, CD
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VEEAM doesn't care about unused space, it only backs up used space.   To clear up space on the hosts drives you have to compress/compact the virtual drive.
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Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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Does Veeam backup utilize the Deduplication on its own, or can we reduce the backup size, even more, when we use Windows Server 2012 R2 Dedupe feature for the NTFS drive ?
@Senior IT System Engineer : Please post a question, this is not your question! and myself or other Expert, will gladly assist.
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Thanks David. A special thanks to you, too, Andrew - for taking the time to do an actual test! Andrew, you didn't delete the data and then run a Veeam backup after the deletion of the 100GB of files did you? If that full backup went right back down to 9GB, that would show for certain that Veeam doesn't backup the space previously occupied by deleted files.
So only 16.7GB is read and backed up, and compressed to 9.2GB after 111GB has been deleted from the VM.

Andrew, you didn't delete the data and then run a Veeam backup after the deletion of the 100GB of files did you?

Yes. see above.


If that full backup went right back down to 9GB, that would show for certain that Veeam doesn't backup the space previously occupied by deleted files.

Yes.

(we cross posted as I was finishing my post)
Ah! Yes, Andrew, when I read your post it was not yet complete so I could not see that last portion of it. I'm now very confident in your answer, and I very much appreciate your help.

As to the last part of my question, you are correct - I was referring to thin disks. As long as Veeam only backs up the used data, I am not worried right now about recovering the space in the datastore. If that becomes important I may make another post in the future. I'll close this item now - thanks Andrew! Your are a real gentleman!
Not a problem, glad you understand. it makes it much easier with pictures.