VMware vSphere

 View Only

  • 1.  Using Snapshots to do in place upgrade of Windows server.

    Posted Apr 20, 2020 03:13 PM

    I need to do an in-place upgrade of Windows 2008 to 2012 R2 and need to use snapshots to perform this.  I can create two snapshots, one pre upgrade and another post upgrade which will be the snap i will be upgrading.  After I do the upgrade, and this where I get confused.  Do i simply delete the snapshot pre-upgrade which leaves me with the upgraded snapshot.  I then am not sure what to do next.  Do I do a delete all or revert? 

    My situation is this:  base --> snapshot 1 Pre-Upgrade  --> snapshot 2 post Upgrade

    I then do in place upgrade of OS on snapshot 2

    I want to keep it as the upgrade has worked

    I assume I delete Snapshot 1 then I have to do something to make the snapshot 2 the running VM but I do not know how.

    Please help.



  • 2.  RE: Using Snapshots to do in place upgrade of Windows server.
    Best Answer

    Posted Apr 20, 2020 03:25 PM

    This should help you understand snapshots: VMware Knowledge Base ​

    Each snapshot is a point in time state (power, memory, and virtual disk) of your VM, and unless you revert the VM to a snapshot all changes will continue to be written to the delta disk created when that snapshot was taken.

    Once you know you do not need to "revert" your VM back to that previous state simply delete your snapshot and all the virtual disk data will be merged back to the parent/original disk file.

    In your case, assuming the upgrade goes well:

    1. Take your snapshot before you start the upgrade process (in case you need to revert)
    2. Do the OS upgrade
    3. Once you're happy that you won't need to revert to the pre-upgrade snapshot, delete it

    If the upgrade fails, you can revert the VM to the pre-upgrade snapshot - you can then try again or delete the snapshot if you decide to cancel the whole process.

    There's little value in creating a post-upgrade snapshot - if all goes well you'd just be complicating things.

    Definitely make sure you delete all snapshots leaving the VM with none once you're done.

    It will still be best to make sure the OS is not accessible to others while you do the upgrade, in case there are data changes not related to the upgrade.

    Snapshots are never substitutes for backups, but can come in useful in situations such as these.