XenServer error after reboot (xenopsd internal error)

Question

How to fix? I can't boot anymore

Jan 24, 2014 10:03:29 AM Error: Starting VM 'CentOS 6 (64-bit)' - 
Internal error: xenopsd internal error: 
VM = 182361af-d10a-d97b-3a65-346d9cec1bcb; domid = 133; 
Bootloader.Bad_error Traceback (most recent call last):

File "/usr/bin/pygrub", line 895, in ?
    part_offs = get_partition_offsets(file)
  File "/usr/bin/pygrub", 
line 105, in get_partition_offsets
image_type = identify_disk_image(file)

File "/usr/bin/pygrub", line 49, in identify_disk_image

fd = os.open(file, os.O_RDONLY)

OSError: [Errno 2] No such file or directory: 
'/dev/sm/backend/94b422b6-3e31-88fb-bc55-99b33de9d89a/36bce863-ba6d-4792-b29d-dc6211bd5e8c'

Answer 1

Probably your server was shutdown improperly, hence, the partition was mounted Read Only. You have to unplug your pbd, check and plug again Read and Write.

That did it for me.

Answer 2

Looks like the VDI of the VM is either corrupted or deleted. From Xencenter click on the VM and go to the respective Storage (Local Storage or Shared) to check that the VDI exists or not. I guess you have to re-create the disk again !

Answer 3

I solved this same problem, where I was unable to get my VDIs to mount in any VM, and booting the VMs failed with the "No such file or directory: /dev/sm/backend" error you're getting.

What worked to fix it was to make a snapshot of each VM, creating a new VM from the snapshot and then deleting the old VM.