I just upgraded my server from 10.04LTS to 12.04 LTS using the server upgrade process documented here: https://help.ubuntu.com/community/PreciseUpgrades.
On boot, I am now dumped to the busybox shell (more on this in a moment). However, if I boot a kernel from the previous release, everything boots fine.
The only thing odd about my configuration is that my boot device is a multi-disk device using RAID1. When I get to the busybox shell, typing "mount /dev/md0 /root" works just fine. I've tried passing in rootdelay=30 and I'm dumped to the shell within 5 seconds of boot.
Unlike the question marked here: Upgraded from 10.04 to 12.04 and grub drops to BusyBox prompt without error I've not been booting with the splash or quiet option, and I've received no complaints about a degraded array. Nonetheless, I've tried booting with the bootdegraded kernel option and this has not worked either.
Any thoughts on what to try?
(And yes, the power supply is plugged in :-) )
Grub version: grub (GNU GRUB 0.97)
Most grub menu.lst options are commented out (to use defaults). Most recent kernel which doesn't work:
title Ubuntu 12.04.2 LTS, kernel 3.2.0-51-generic-pae root (hd0,1) kernel /boot/vmlinuz-3.2.0-51-generic-pae root=/dev/md0 ro initrd /boot/initrd.img-3.2.0-51-generic-pae quiet
Most recent kernel which does work:
title Ubuntu 12.04.2 LTS, kernel 2.6.32-46-generic-pae root (hd0,1) kernel /boot/vmlinuz-2.6.32-46-generic-pae root=/dev/md0 ro initrd /boot/initrd.img-2.6.32-46-generic-pae quiet
garrett@stargate:/boot/grub$ sudo mdadm --detail /dev/md0 /dev/md0: Version : 0.90 Creation Time : Sat Dec 16 22:27:17 2006 Raid Level : raid1 Array Size : 57609024 (54.94 GiB 58.99 GB) Used Dev Size : 57609024 (54.94 GiB 58.99 GB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Mon Sep 2 17:02:27 2013 State : clean Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 UUID : 5c92f0d9:9cf5be95:03611c5e:a540b92f Events : 0.24172972 Number Major Minor RaidDevice State 0 8 18 0 active sync /dev/sdb2 1 8 2 1 active sync /dev/sda2
Md device data as seen by the kernel:
garrett@stargate:~$ cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid1 sda2 sdb2 57609024 blocks [2/2] [UU] unused devices: <none>