I am trying to convert a 6 disk raid6 mdadm array to a 6 disk raid10 array. After hitting an
mdadm: Impossible level change requested, I decided to try with raid5, and so ran
mdadm --grow --level=5 and then
mdadm --grow /dev/md0 -n 5 successfilly. However, when I ran
mdadm --grow /dev/md0 --level raid10, I hit the same error again. I decided to go from raid5 -> raid4 -> raid0 -> raid10, but for this too work, I need to have 3 disks at the raid0 stage, as I only have 6 disks.
However, after I managed to resize the array to be the suggested size for
mdadm --grow /dev/md0 -n 3, I get the following error:
mdadm: Cannot set new_offset for /dev/sda12
When I remove
/dev/sda12 from the array, I get the same error, but for a different disk.
How do I fix/work around this error, or do I have to nuke the array and start a new one?