Recovering an ZFS vm

[Peter Grehan]

Hi Randy,

> I have a Centos vm that has suddenly stopped booting. At the console, grub
> tells me the following if I attempt to list any of the available partitions.
> 
> error: not a correct XFS inode.
> error: not a correct XFS inode.
> error: not a correct XFS inode.
> error: not a correct XFS inode.
> error: not a correct XFS inode.
> Filesystem type xfs, UUID 7652ffda-f7c5-408a-b0ce-b554b66fc2e5 - Partition
> start at 2048 - Total size 2097152 sectors
> grub>
> 
> Is there an easy way to recover this? This has happened more than once.
> Just so happens there is something on this image I would like to have
> access to...

  Looks like the grub partition was upgraded to the version of XFS that 
has the CRC feature enabled (7.2 ?). Unfortunately this feature is not 
understood by grub-bhyve :(

  One way to recover the disk is to create a new VM with the most recent 
CentOS, but using UEFI for the bootloader. Then, add this disk to the 
guest, and from within the guest I think you can run an XFS utility that 
will disable the use of CRCs on that partition.

  The proper fix would be for grub-bhyve to be updated to the latest 
version of grub2, though a workaround is to create guests with UEFI and 
not use grub-bhyve.

later,

Peter.