chroot to md0 for "rescue" from live CD???
 

By way of not having Pin preferences set properly, I just accidentally upgraded my libc6 library to "breezy" and have fuX0red my system.

My mistake was instantly obvious. Any references to the filesytem failed...the system slowly imploded and eventually locked when I tried to switch to tty1.

Selecting an older kernel or (recovery mode) results in a kernel panic as soon as it goes about 15 lines or so then:

VFS: Cannot open root device "md0" or unknown-block(0,0)

...this is for my oldest kernel "Ubuntu, kernel 2.6.10-5-amd64-generic (recovery mode)".

My most recent kernel "Ubuntu, kernel 2.6.11-1-amd64-k8 (recovery mode)" rocks along until:


mdadm: /devfs/md/0 has been started with 4 drives.
Stopping tasks: ====|
Freeing memory... done (1174 pages freed)
Restarting tasks... done
kjournald starting. Commit interval 5 seconds
EXT3-fs: mouned filesystem with ordered data mode.
exec: 428: chroot: not found
Kernel panic - not syncing: Attempted to kill init!

And that's it folks.

I am booting off of a USB drive and have root on md0 raidset (raid 5, 4 drives) with tmp and swap being separate LVMs spanned across the same drives in separate partitions.

I understand that I could *reinstall* from scratch...but I'm fairly certain that their should be a way to boot off of a "Live CD" mount/chroot my actual root dir on /dev/md0 and then "roll back" my boo boo.

I think I'm heading in the right direction, but I could really use some handholding, as I'm nervous as hell to have to start over...it took me a month and a half of weekends to get it to the state where it is (my first desktop!):

AMD64 3800+ 4x SATA 250GB NVidia Geforce 6800 Ultra, Dual Head video, transcode working, mplayer all custom scripted up with home brew perl interface to handle "deregionized" lite-on DVD players and adjust according to language, region, and format (pal vs ntsc), mythtv running the whole show...

I really really really really wanted to show this at the next LUG meeting (my first!)

Help me out here guys and show me how tight the Ubuntu community is! Help me to share my (few but tasty) morsels of knowledge!

:-)