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).