When I upgraded my normal 1 harddisk installation to raid-1, I needed to write following to the menu.lst.
title Debian GNU/Linux, RAID kernel 188.8.131.52
kernel /boot/vmlinuz-184.108.40.206 root=/dev/md0 md=0,/dev/hda1,/dev/hdc1 ro
title Debian GNU/Linux, RAID recovery kernel 220.127.116.11
kernel /boot/vmlinuz-18.104.22.168 root=/dev/md0 md=0,/dev/hdc1 ro
I wrote this under of "### END DEBIAN AUTOMAGIC KERNELS LIST"
I manually disconnected harddisk no. 1 and it still started. Then did same for harddisk no. 2 and it still started.
I also have Debian in another computer, which has been installed directly to RAID, but I haven't checked if it is able to boot from both harddisk. It has different configuration:
title Debian GNU/Linux, kernel 2.6.22-2-686
kernel /boot/vmlinuz-2.6.22-2-686 root=/dev/md0 ro
I think your raid-partitions are fine, but grub is messed up. If you can mount your md0 with sysresccd, you should be able to see state of harddisk with
After it will work again, please make extra backup of first 63 sectors with dd.
dd if=/dev/hda of=/your_directory/grub_backup_hda.bin bs=512 count=63
dd if=/dev/hdc of=/your_directory/grub_backup_hdc.bin bs=512 count=63
or something like that.