Inactive raid1 partition failure

[Alex]

Hi,
I have a fedora21 system with three md RAID1 arrays. I had used this
system to temporarily access an external array connected to an LSI
controller in the system. So I inserted the LSI controller, accessed
the data on the disks connected to it, and removed the controller from
the system.

Now, all three md RAID arrays are in some type of degraded state:

# cat /proc/mdstat
Personalities : [raid1]
md2 : inactive sdb1[1](S) sdc1[4](S)
      1953519616 blocks super 1.2

md0 : active raid1 sda1[0]
      511988 blocks super 1.0 [2/1] [U_]

md1 : active raid1 sda2[0]
      237566840 blocks super 1.2 [2/1] [U_]
      bitmap: 2/2 pages [8KB], 65536KB chunk

Thankfully the system boots. The inactive array, md2, is connected to
/var/backup, so I just commented it out of /etc/fstab to get the
system to boot.

It appears the devices were somehow impacted by the LSI controller,
and now the partitions/devices have been reordered.

How do I realign these slices to rebuild the array?

Thanks,
Alex