Does this sound like a reasonable plan?  After backing up all files and 
booting to a Live CD:

(1) mount /dev/sda and /dev/sdb
(2) Remove /boot directory from / partition on both sda and sdb
(3) Install grub in /boot parttions on both drives.
(4) mount /boot partitons of both sda and sdb
(5) copy known-working kernel and two newest installed kernels to /boot 
partition from backup media (formerly in /boot of / partition)
(6) make sure /boot partition is mounted in fstab
(7) /boot partition should also be in the RAID1

Does that sound like it would fix it?  Any ideas?

More info below, if you're interested.  ;-)



I think my problem is related to this:

http://unix.stackexchange.com/questions/3623/installing-grub-2-on-mdadm-which-device?rq=1

I'm pretty sure I installed grub on only one of the two drives.  Then I 
didn't mount the /boot (I don't even know how to do that!).

So now I have Ubuntu installed so that there is a /boot directory in the / 
partition, and there is a /boot partition.  The / partition (and thus 
/boot *directory*) is in the RAID1, but the /boot partition is not in the 
RAID1.


/dev/sda and /dev/sdb are identical and both show this with parted -l:

Sector size (logical/physical): 512B/4096B
Partition Table: gpt

Number  Start   End     Size    File system  Name   Flags
  1      10.5MB  220MB   210MB                /boot  bios_grub
  2      220MB   34.6GB  34.4GB               swap   raid
  3      34.6GB  3000GB  2966GB               /      raid


df doesn't show a /boot partition...

Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/md1       ext4      3.0T  296G  2.6T  11% /
udev           devtmpfs  8.4G   13k  8.4G   1% /dev
tmpfs          tmpfs     3.4G  902k  3.4G   1% /run
none           tmpfs     5.3M     0  5.3M   0% /run/lock
none           tmpfs     8.4G   29M  8.4G   1% /run/shm
/dev/sde1      fuseblk   1.6T  947G  554G  64% /media/New Volume
/dev/sdd1      fuseblk   2.1T  319G  1.7T  16% /media/HD-CLU2


...and the /boot *directory* in / is already using about 50% more space 
than /boot partition would allow:

$ du -sm /boot
341     /boot

$ df -HT /boot
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/md1       ext4  3.0T  296G  2.6T  11% /


$ \ls -1v /boot | cut -d'-' -f-2 | uniq -c
      15 System.map-3.2.0
      15 abi-3.2.0
      15 config-3.2.0
       1 grub
      15 initrd.img-3.2.0
       1 memtest86+.bin
       1 memtest86+_multiboot.bin
      15 vmlinuz-3.2.0

So it looks like Ubuntu updates have installed 15 kernels in the /boot 
directory in /.  The big files are the ones beginning with initrd.img at 
about 14.6 MB apiece.  The grub directory takes up only 5 MB.

Best,

Mike