I think it was telling me...
$ cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sda1 1464845671 blocks super 1.2 [2/1] [U_]
I tried lots of stuff, but couldn't get it to be an 'active' [UU] raid again... stuff like...
$ mdadm --assemble /dev/md0 /dev/sda1 /dev/sdb1 mdadm: /dev/md0 assembled from 1 drive - need all 2 to start it (use --run to insist).
The bottom of my /etc/mdadm/mdadm.conf looked like this:
ARRAY /dev/md0 metadata=1.2 name=Mycomp:0 UUID=6e7efcee:e9bc12a6:cb210f4f:0f0b4736
Which I believe was generated by $ mdadm --detail --scan >> /etc/mdadm/mdadm.conf.
Now I'm re-mirroring the drives... (ughh, such a pain...) and starting over, to make sure it was originally a [UU] raid, and it seems like it is in fine condition, but now, how do I perform this 'drive unplugging' test and rebuild the array properly? Am I missing a step/ conf configuration?