On 03/27/2017 10:14 AM, Hendrik Boom wrote:
>
> Indeed, I have one RAID with old metadata with only /boot on it.
> Another with new metadata containing many LVM partitions.
>
you can erase the partitions (and metadata) on the outdated disk,
booting from a rescue CD (or live CD), with the updated disk
disconnected, that way you don't risk any accidental RAID operation.
Then boot from the updated disks, and then you can re-create the
partitions and use mdadm to fix it.


--
Héctor González
cacho@???