HOMEPAGE FORUMS NEWS DOCUMENTATION SCREENSHOTS
SystemRescueCd forums
View unanswered posts | View active topics It is currently 31 Jul 2014, 17:34



Post new topic Reply to topic  [ 2 posts ] 
 Ubuntu Hardy Server recovery not working 
Author Message

Joined: 05 Jun 2008, 06:31
Posts: 1
Post Ubuntu Hardy Server recovery not working
Hi all,

I installed an Ubuntu Hardy Server which worked fine. The root was on a software raid1 /dev/md0 and the swap on another software raid1 /dev/md1.

The only problem is I made a mistake and it didn't work anymore.

Fortunately I knew it could happen, so when it was working I made an image of the root with partimage using SystemRescueCD.

When the Ubuntu Server was broken, I recovered using this image and put it back on the raid /dev/md0 which was the root of my system. Then I installed grub on the MBR in each disk.

When I reboot, grub runs fine. But the Ubuntu Server doesn't want to start and I have this error message:
ALERT DOES NOT FIND MD0
and it starts in busybox mode.

Unfortunately if I boot SystemRescueCD it finds perfectly my 2 software raid1.

I've checked the files mdadm.conf and menu.lst, and they seem correct.

Anyone knows why the recovered Ubuntu Hardy Server from a working image doesn't want to start? Why can't it find /dev/md0?

Thanks.


05 Jun 2008, 06:48
Profile

Joined: 18 Nov 2006, 13:09
Posts: 89
Post 
When I upgraded my normal 1 harddisk installation to raid-1, I needed to write following to the menu.lst.

Code:
title           Debian GNU/Linux, RAID kernel 2.6.18.1
root            (hd0,0)
kernel          /boot/vmlinuz-2.6.18.1 root=/dev/md0 md=0,/dev/hda1,/dev/hdc1 ro
savedefault

title           Debian GNU/Linux, RAID recovery kernel 2.6.18.1
root            (hd1,0)
kernel          /boot/vmlinuz-2.6.18.1 root=/dev/md0 md=0,/dev/hdc1 ro
savedefault


Notice md=0,/dev/hda1,/dev/hdc
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:

Code:
title           Debian GNU/Linux, kernel 2.6.22-2-686
root            (hd0,0)
kernel          /boot/vmlinuz-2.6.22-2-686 root=/dev/md0 ro
initrd          /boot/initrd.img-2.6.22-2-686
savedefault


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

Code:
cat /proc/mdstat


After it will work again, please make extra backup of first 63 sectors with dd.

Code:
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.


21 Jun 2008, 11:42
Profile ICQ
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 


Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group.
Designed by Vjacheslav Trushkin for Free Forums/DivisionCore.