Ubuntu Installation :: 10.04->11.04:often Get Degraded Raid Error At Boot?

I recently upgraded from 10.04 to 11.04 and I now often get boot messages about a degraded raid.

I'm fairly experienced, but I'm confused which raid it is talking about. I have a raid5 array, but I don't boot of that, and it seems fine when I finally get it to boot. Previously, I didn't have any other raid arrays[1], but now I seem to have two others called md126 and md127, they both seem to be degraded. Where did they come from?

[1] I *do* have two 80GB drives that I was booting from in RAID1, but that was a looong time ago, and I have since only booted from one of them. The partition table indeed shows partitions 1 and 5 are raid autodetect and /proc/mdstat shows they are degraded ([U_]). Could it be that this is causing the problem? If so, why has this only started to happen since the upgrade from 10.04 to 11.04?Anyway, perhaps it is a good idea to add in that second disk to the raid1 array. If so, how to do that? Note that, I've also noticed that when I boot and get to the screen when I select from the different kernel versions, I now get a couple of really old ones too - my thought is that these are from the raid1 disk that I stopped using. If I add it to the array, how can I be sure it will mirror in the correct direction?

It could be that I have fairly recently plugged in that second RAID1 disk, after a long time of not having enough spare sata sockets (I switched my RAID5 array from 8 disks to only 3 disks, so suddenly had a lot more spare sockets).