Migrating existing RAID1 volumes to bigger drives

Every once in a while hardware needs to be replaced. Sometimes boards, sometimes CPUs and sometimes drives. Drives are the ones most difficult to replace as they hold all that precious data one does not want to lose.

I personally hate reinstalling stuff; so I try as much as possible to “migrate” my data around. In this tutorial I’ll be replacing two drives under a RAID1 array with two newer bigger drives (and resize the array accordingly).

Erase RAID metadata from (previously used) disk

I recently attempted to install a fresh CentOS on a pair of recycled (previously used in a different linux sistem) hard disks.

Of course I got the classical message that the disks already had RAID metadata on them: “Disk contains BIOS metadata, but is not part of any recognized BIOS RAID sets. Ignoring disk sda”