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  • Esx 3.5 - Snapshot Question

    Hi,

    I'm starting to work on esx and it's virtual infrastructure, so ... i'm a newbie on this.

    Checking one of our client's esx server, i've noticed that is running out of free space on it's datastore, due to some big snapshot files of a single VM.

    The esx installed is esx foundation v.3.5 ( 176894 ).

    Checking the snapshot manager i have this situation (see attached image).
    I dont know why it states the i'm running a level bellow some snapshot unactive.

    Now, i want to delete all the snapshots, merging them to the real vmdk files.

    If i take a brand new snapshot, and then issue the "delete all" command, will this delete all the previous snapshots merging the disk to the last snapshot ?

    thanks in advance.


    Stefano
    Attached Files

  • #2
    Re: Esx 3.5 - Snapshot Question

    Here's how i did.

    I've shutted and copied the VM files to a secondary datastore as backup.

    After trying to delete all the snapshots via the VI client ( snapshot manager -> delete all), the esx reported the delete snapshots progress at 95% for about 50mins, after that i couldnt manage the esx with the vi-client due to tiemout error and slow response time.

    Even trying to delete the snapshots with the cli with no success.

    So.

    I've restarted the esx, deleted the original VM, imported tot eh invenroty the backup VM ( renaming the display name ) and booted i with the vmware converter boot cd.

    I did a conversion from the backup vm to a new vm ( all in the same esx ).

    After converting 60Gb of machine, about 5 hours i get the same machine as before without the hassle of big snapshots.

    Comment


    • #3
      Re: Esx 3.5 - Snapshot Question

      I'm glad you've sorted it out for now.. however, I'll give you some info I've discovered on snapshots for future ref.

      Say you have a 20GB vmdk file, and you're using about 8GB of it (basic system install, maybe a few other tools)
      As you go about your daily business on the virtual guest, it will keep writing data to the VMDK file, maybe not a lot, depends. For instnace- if you dump a 2GB file on the C: drive, now you'll be using 10GB of the VMDK file.
      Let's assume, at this point, you take a snapshot.
      ESX creates hte Snapshot file for you, and starts writing new changes to that snapshot file. So now, you dump another 2GB file on the C: drive. You have a 10GB VMDK file, and a 2GB snapshot file. A snapshot will continue to grow.. and grow.

      I have a client who has snapshots that sometimes get locked up for some reason. The file grows to 50GB or there abouts, takes up the last of the available space on the VMFS volume, and can't write to the snapshot any more.. at this point, it breaks down and cries, shutting down the virtual guest as it has no space to write more changes.

      There are two ways to handle snapshots - you can delete them, which merges them into the base VMDK file, or you can revert them - which deletes the data.
      Depending on the size of the snapshot, deleting, or reverting, WILL take large amounts of time. Just Be Patient.

      Now for some feedback on how deleting snapshots merges it back in.. (this is from esx2.5, but is mostly relevant..)
      You create a snapshot, then decide to delete it.
      ESX pauses the guest, and the snapshot file, for a split second, and creates a SECOND snapshot. After unfreezing, it continues to write into this 2nd snapshot. At the same time, it then merges down the first snapshot, into the original vmdk file. Then, it will merge in the changes from the second snapshot. Usually, you can expect at the very least a pause of the guest here.

      The theory behind this is, the changes that go into the second snapshot, aren't much, so will happen much quicker.

      Ultimately, reverting or deleting snapshots, will cause load, and should ideally be done when the guest is not in use...


      (if anyone thinks I'm wrong on my deductive reasoning, then please feel free to tell me !
      Please do show your appreciation to those who assist you by leaving Rep Point https://www.petri.com/forums/core/im.../icon_beer.gif

      Comment


      • #4
        Re: Esx 3.5 - Snapshot Question

        Today I learned:
        Pressing the delete or delete all button will merge the files and will take the machine out of snapshot mode.

        When pressing the go to button you will go back in time, however you will not get out of the snapshot mode. So a new snapshot will be created and it continue using the new snapshot.The Goto button will only revert to a previous state. Hitting the delete button will then finally delete the snapshot and will get you out of the snapshot mode.

        You are better off deleting them and only take a snapshot when needed. If you are done using the snapshot, delete (merge) it or revert to it and then delete it.

        A couple of Powershell scripts which might have helped you:
        http://www.ntpro.nl/blog/archives/29...ot-hunter.html
        http://www.ntpro.nl/blog/archives/29...t-Remover.html
        (He is actually my teacher too )
        Marcel
        Technical Consultant
        Netherlands
        http://www.phetios.com
        http://blog.nessus.nl

        MCITP(EA, SA), MCSA/E 2003:Security, CCNA, SNAF, DCUCI, CCSA/E/E+ (R60), VCP4/5, NCDA, NCIE - SAN, NCIE - BR, EMCPE
        "No matter how secure, there is always the human factor."

        "Enjoy life today, tomorrow may never come."
        "If you're going through hell, keep going. ~Winston Churchill"

        Comment


        • #5
          Re: Esx 3.5 - Snapshot Question

          We had a simliar situtation where we could not merge the snapshots. We booted to a CD, took an image of the VM then restored the image to a new VM. Worked great.

          PS. Don't snapshot a DC.
          Last edited by Garen; 16th February 2010, 22:59.

          Comment


          • #6
            Re: Esx 3.5 - Snapshot Question

            Oh about that.. I heard that the snapshot deletion/merging process is still continuing on the ESX host, however the vCenter server times out...
            So if you let it run, it should resolve it by itself... Sounds like being patient?
            Marcel
            Technical Consultant
            Netherlands
            http://www.phetios.com
            http://blog.nessus.nl

            MCITP(EA, SA), MCSA/E 2003:Security, CCNA, SNAF, DCUCI, CCSA/E/E+ (R60), VCP4/5, NCDA, NCIE - SAN, NCIE - BR, EMCPE
            "No matter how secure, there is always the human factor."

            "Enjoy life today, tomorrow may never come."
            "If you're going through hell, keep going. ~Winston Churchill"

            Comment


            • #7
              Re: Esx 3.5 - Snapshot Question

              yea - if you let it run, it does eventually complete
              (at least, with our 50GB situation it does)
              Please do show your appreciation to those who assist you by leaving Rep Point https://www.petri.com/forums/core/im.../icon_beer.gif

              Comment

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