Hyper V VM stuck in reboot loop - Server 2012R2

Discussion in 'Virtualized Computing' started by Stealtharsenal, Mar 19, 2017.

  1. Stealtharsenal

    Stealtharsenal n00bie

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    Aug 5, 2016
    Hello everyone,

    Looking to get some help with one of my VM's currently running on Server 2012 R2. Sometime early yesterday morning (Saturday morning) my Exch VM crashed and got stuck in a reboot loop. Everytime it would try to boot into its install of Server 2012 R2, it would bsod indicating Inaccessible Boot Drive. I am accessing the machine remotely as I can access the Host, and the DC VM without issues. I did the typical shut down and reboot and manual restarts incase it was just a bug. That did not work. I then was entered into the recovery console where I tried last known good configuration, all the different safe modes, etc and still stuck in this boot loop. With that, this morning with a clear head, I took a look at Server Manager on the Host and looked at the Hyper -V Events and saw the following:

    ID 18590

    -Exch12 has encountered a fatal error. THe guest operating system reported it failed with the following error codes: Errorcode 0: 0x7B, Errorcode1: 0x5F16D8D0, Errorcode2: 0xC0000034, Errorcode3: 0x0, Errorcode4: 0x0

    With that said, when I am in recovery console and I tried to enter the command prompt to run say chkdsk or run a repair command, the recovery console has me select my administrator account and asks for a password. I enter my normal password to access the host and all the vm's and it is not accepted. Not sure what is going on here. Also when I look at Hyper-V on the host and look at the Virtual Hard disks, I can see the data file for the VM having issues. When I check disk (on the issue VM) it returns back the Location, File Name, Current File Size and Max Disk Size. With that, I feel the integrity of the data is intact.

    What else can I do to try and remedy this VM issue. Its our exch, so we need to get it operational again.

    Thank You for the help.
     
  2. Simplyfun

    Simplyfun Gawd

    Messages:
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    Dec 17, 2016
    couple of things come to mind, these kind of boot loops are common when you have snapshots going and run out of physical disk space. I have also seen similar errors resolved by reinstalling Microsoft Hyper-V Storage Accelerator drivers.

    More worrying if your passwords aren't being accepted then the possibility exists that your VM has been corrupted beyond repair by some underlying physical layer issue or possibly (I've also seen this) key files in the VM have been hijacked by ransomware and encrypted.

    Normally, you restore a base level VM, mount the drive and migrate the data over either from the VM or from your known good backups as the easiest path to get it running.
     
  3. Stealtharsenal

    Stealtharsenal n00bie

    Messages:
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    Aug 5, 2016
    Simplyfun

    Thanks for your input. We ended up fixing it. The VM (the install of Windows in particular) was beyond repair. We were able to rebuild our exchange server in a new VM and migrate the database over via repair and salvage all of our data. We are now going to set up a new type of disaster recovery to prevent this from happening again.
     
    Simplyfun likes this.