The never-ending upgrade: RAID problem/question

[lug at the-leveys.us (Don Levey)]

I won't bore you all with the full story of this weekend's upgrade of my
home server; that's a tale for more time and more beer.  Some may recall
that I had a partition on my mail hard drive fry, and I solicited advice
about the upgrade.  Much of this centered around RAID.

Well, I already had two RAID-1 partitions on two other drives on the
machine, md0 and md1.  Everything is working now, but... apparently, the
/dev/hdb drive has dropped out of the config (leaving only /dev/hdc).  I can
access it via fdisk, so I know it's there and being read.  But doing a cat
of /proc/mdstat gives me:

	[don at davinci ~]$ cat /proc/mdstat
	Personalities : [raid1]
	md1 : active raid1 hdc2[0]
	      35840768 blocks [2/1] [U_]

	md2 : active raid1 hdd1[1] hda1[0]
	      497856 blocks [2/2] [UU]

	md3 : active raid1 hdd2[1] hda2[0]
	      34186240 blocks [2/2] [UU]

	md4 : active raid1 hdd3[1] hda3[0]
	      24418688 blocks [2/2] [UU]

	md5 : active raid1 hdd5[1] hda5[0]
	      94735168 blocks [2/2] [UU]

	md6 : active raid1 hdd6[1] hda6[0]
	      2449792 blocks [2/2] [UU]

	md0 : active raid1 hdc1[0]
	      81377024 blocks [2/1] [U_]

	unused devices: <none>

As you can see, the two original RAID partitions only contain hdc.  So...
what should I look at, what should I do, to make this whole again?  As I
mentioned, things *are* working now, but as the redundancy is why I mirrored
those drives in the first place (the whole music collection, as well as all
the photos of the kids) I'd kinda like to get that back.

Thanks for your help,
 -Don