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We recently lost an NFS server. It was used to export a drive with ISO files for use in XenServer patching / updating / etc. The server has been replaced but the mounted drive can't be removed from XenCenter or via the command line.

What I've tried:

(using these instructions):

  1. xe sr-list name-label=<NFS mount>
  2. xe pbd-list sr-uuid=<UUID of volume>
  3. xe pbd-unplug uuid=<UUID of mount point>

Error message:

Error code: SR_BACKEND_FAILURE_140 Error parameters: , Incorrect DNS name, unable to resolve.,

The volume no longer appears in /etc/mtab but Xen refuses to let go of it.

Suggestions on where else to look?

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up vote 0 down vote accepted

FWIW: I added an entry in /etc/hosts to point to the new (replacement server). Then the sequence of commands above will work and you can proceed to the 'forget' option in XenCenter.

If you are hitting this problem but getting the "General backend error" message try this. Essentially you'll need to get rid of the mounted volume on your own and then clean up Xen.

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