VMWare Cloning to Change Disk Provisioning - How Painful is It?



  • I have 3 ESXi hosts with all local storage, and each is OBR10. On one host in particular, storage space is at a premium. In my early days with VMWare I setup thick provisioning on a particular VM and provisioned WAY too much space for it in the beginning. This happens to be the Solidworks ePDM server we use in our environment. It does run SQL, but even so, there is probably 300 - 400 GB of free space to be freed by either changing to thin provisioning or just shrinking the size of the vHD. The only way I know to do this is by cloning the VM and changing the provisioning or just sticking with thick provisioning and not allocating so much space this time.

    How painful is this to do? I have not done it but have seen some articles online about it and just wanted to ask for others to share their experiences in the matter.



  • I should also add that performance for this VM has been acceptable to the Engineering team. I'm just interested in claiming more of the unused space than anything.

    And we're running ESXi 5.5U1.



  • I don't know how you'd do it with Veeam, but with Unitrends you do a full backup of the VM as a physical machine, do a Bare Metal restore on a newly sized VHD, then a file level restore, then, in this case, a SQL restore. I know, however, that Veeam is 100% virtual. That's just my 2 cents. You could always get a UEB Free and do this one machine this one time. It'll give you a good taste of Unitrends too.



  • @ajstringham said:

    I don't know how you'd do it with Veeam, but with Unitrends you do a full backup of the VM as a physical machine, do a Bare Metal restore on a newly sized VHD, then a file level restore, then, in this case, a SQL restore. I know, however, that Veeam is 100% virtual. That's just my 2 cents. You could always get a UEB Free and do this one machine this one time. It'll give you a good taste of Unitrends too.

    I'm thinking I can do it in VMWare without any assistance from Veeam. Or at least that was my understanding that I could.



  • @NetworkNerd said:

    @ajstringham said:

    I don't know how you'd do it with Veeam, but with Unitrends you do a full backup of the VM as a physical machine, do a Bare Metal restore on a newly sized VHD, then a file level restore, then, in this case, a SQL restore. I know, however, that Veeam is 100% virtual. That's just my 2 cents. You could always get a UEB Free and do this one machine this one time. It'll give you a good taste of Unitrends too.

    I'm thinking I can do it in VMWare without any assistance from Veeam. Or at least that was my understanding that I could.

    Not sure how you'd change from thick to thin though.



  • If you got the space, why not do it through the OS? Robocopy/clone over the drive to a thin provisioned VMDK, then delete the thick provisioned VMDK. Then modify the OS to make the "new" drive the same letter as the "old" drive.

    Myself, I would just clone the thing using something like DriveXML. Quick and dirty, just how I likes it.


  • Service Provider

    No external tools needed, the directions for going from thin to thick or thick to thin are here:

    Changing VMware vSphere Drive Provisioning from Thick to Thin



  • I thought Windows allowed you to grow/shrink partitions these days (except the system partition)?


  • Service Provider

    @Dashrender said:

    I thought Windows allowed you to grow/shrink partitions these days (except the system partition)?

    That does not affect VM thin/thick provisioning. that is the guest inside.



  • @JaredBusch said:

    @Dashrender said:

    I thought Windows allowed you to grow/shrink partitions these days (except the system partition)?

    That does not affect VM thin/thick provisioning. that is the guest inside.

    Understood, but you can grow/shrink partitions in VMWare as well - though - now that I put more thought it into, perhaps shrinking a partition in VMWare would be bad since it might shrink area that has data instead of free space area.

    original though was, use windows to shrink partition, then use VMWare to shrink disk


  • Service Provider

    @Dashrender said:

    I thought Windows allowed you to grow/shrink partitions these days (except the system partition)?

    It does, so does Linux. But we are not talking about partitions at all, nor Windows.


  • Service Provider

    @Dashrender said:

    Understood, but you can grow/shrink partitions in VMWare as well

    No partitions here. We are talking about a file, not a partition.



  • @scottalanmiller said:

    @Dashrender said:

    Understood, but you can grow/shrink partitions in VMWare as well

    No partitions here. We are talking about a file, not a partition.

    THINKS - aw yes.. you're right - I see my missing logic.