I have (had) a RAID 1 array (2 disk mirror) and one of the disks, sda, failed. So I've replaced the bad disk with a new one, but seem to be stuck on how to get the second drive back up and running as part of the array.
The system is running Ubuntu Server 9.04 and was configured as follows:
MD0 => sda1,sdb1
MD1 => sda3,sdb3
MD2 => sda2,sdb2
mdadm --detail /dev/md0
shows two drives:
0 /dev/sdb1 "Active Sync"
1 [nothing] "Removed"
MD1 and MD2 look the same.
The tutorial I found says to mark each partition as failed using the command:
mdadm --manage /dev/md0 --fail /dev/sda1
But, since the drive is not there, I get:
mdadm: cannot find /dev/sda1: No such file or directory
Can I skip the failing step? Or is there some other way to fail a partition that's no longer present? Or if I copy the partition table from the good old drive to the new one, will it automatically pick up that it's the replacement?
I'm new at this and don't want to screw it up. :)