I recently experienced a problem with my debian Installation. Now I will try to explain, what I did to correct the problem.
The Setup: I have a debian 2.6 installation, with 3 two terabyte harddrives running in a RAID5 setup, with a grub2 bootloader. The boot partition is also a RAID5 partition.
The Problem: I have installed the bootloader on all three harddrives, using the following commands:
But when I remove /dev/sda, Debian will not boot. It restarts before the bootloader menu appears.
The Solution: I found out, that when I use the grub-install command, it does not copy the graphicial Debian splash screen to the current disk. Therefore the splash screen only is present on /dev/sda, and when this is removed it fails. My workaround was to disable the graphical splash screen. This is done the following way:
make sure that these lines are not commented out
# Uncomment to disable graphical terminal (grub-pc only)
And then it worked. Now I can remove a random disk, and it still boots. WOOHUU!
I do not know, it this i a bug i my version of Debian, I have not tried upgrading the installation.