After a power failure, my machine comes up but doesn't mount the raid disk because it isn't found (correctly). Using mdadm --examine on the partitions making up the raid device, I found that they are there, but with a different UUID and a new name after the power fail. The new name is clearly a bogus string from some other memory/disk location before the crash. I don't think it had a name before because it would previously auto-assemble on /dev/md0.
Linux actually auto-assembled the raid device, but I didn't notice at first because it was on a new device name (/dev/md/NEW_NAME), and had a new UUID. I was able to manually e2fsck check it, mount it and all of the data is there and good. Now I want to restore it to the old device, and old UUID. I know how I can do this by destroying it and recreating it, but that requires backing up and restoring the data. Actually I already have a day-old backup, so I could skip that part, but this is a really big drive and even the restore will be many hours.
How to fix this the quick way: fixing the raid superblock(s) without touching the data?