SR_BACKEND_FAILURE_46 The VDI is not available

May 18, 2013 at 6:20 pm  •  Posted in Xenserver by  •  4 Comments


SR_BACKEND_FAILURE_46: [ ; The VDI is not available opterr=VDI (UUID) already attached RW;]

This occurred when a Server 2003 guest hard locked and was killed with /opt/xensource/debug/xenops destroy_domain –domid $domid

{adinserter 1}When I destroyed the domain, the lock that had been placed on the guest was never released. The lock stops other hosts within the pool from starting the guest at the same time. In order to get the guest running again quickly, I took a snapshot and built a new VM from it. This way I could troubleshoot the issue later in the day.

How to Resolve SR_BACKEND_FAILURE_46

  1. Make note of the UUID of the VDI experiencing the issue. The VDI UUID is in the error “opeterr=VDI (UUID)”. IMPORTANT – If you have more than one disk associated with the guest, make sure to get ALL the associated VDI UUID and Virtual Block Device(VBD) device numbers along with the mode and bootable status for each.
    • xe vbd-list vm-uuid=$vmUUID params=vdi-uuid,device,bootable,mode
  2. Determine which Storage Repository(SR) is holding the VDI.
    • xe vdi-list uuid=$UUID params=sr-uuid
  3. Remove the association of the VDI to the guest. Do this with all discovered VDI from the first step.
    • xe vdi-forget uuid=$vdiUUID
  4. Run an sr-scan and watch SMlog for any errors.
    • xe sr-scan uuid=$srUUID; tail -f /var/log/SMlog
  5.  Recreate a Virtual Block Device via the command line or from Xencenter. This acts as the virtual SATA cable between the VDI and the guest. The device number, bootable, and mode may vary. However, you should have all the needed information if you used the command in the first step.
    • xe vbd-create vm-uuid=$vmUUID bootable=true device=0 type=disk vdi-uuid=$vdiUUID mode=RW
  6. Start the guest.
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  1. Pingback: The VDI is not available SR_BACKEND_FAILURE_46 in Xenserver 6.1 | XenLens

  2. Srinivas / September 24, 2013 at 5:28 am / Reply

    Your tutorial fixed my issue completely. Thanks for making the note regarding multiple drives on a VM, I followed a tutorial previously which failed to mention that information.

  3. akismet-126009b010bd069c3ce497e54d56c31e / April 4, 2014 at 9:57 am / Reply

    Awesome! thanks so much!

    • Bl_nK / April 4, 2014 at 1:31 pm / Reply

      Glad I could help!

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