Restore MBR and setup Grub correctly

ilw · 03-04-2009, 03:37 PM

A couple of days ago one of my hard drives died (it was master on the primary ide) and my computer no longer gets past the initial POST i.e. it gets to the stage where normally Grub would start doing stuff and just hangs.
From the little i know i'd guess that losing the hard drive has possibly meant i've lost or corrupted my MBR and has probably screwed up my Grub settings as well... I've tried following various instructions from the interweb, but nothing has changed - I think my almost total lack of knowledge of what i'm doing isn't helping so much.

Any help/advice would be appreciated! I've included some of the config info and results from common commands below

Code:

grub> find /boot/grub/stage1
 (hd0,0)


grub> geometry (hd0)
drive 0x80: C/H/S = 38913/255/63, The number of sectors = 625142448, /dev/sda
   Partition num: 0,  Filesystem type is ext2fs, partition type 0x83
   Partition num: 1,  Filesystem type unknown, partition type 0x82
   Partition num: 2,  Filesystem type is ext2fs, partition type 0x83

grub> geometry (hd1)
drive 0x81: C/H/S = 19457/255/63, The number of sectors = 312581808, /dev/sdb
   Partition num: 0,  Filesystem type unknown, partition type 0x6

grub> geometry (hd2)
drive 0x82: C/H/S = 24792/255/63, The number of sectors = 398297088, /dev/sdc
   Partition num: 0,  Filesystem type is ext2fs, partition type 0x83

I've tried running the setup command in grub, but it doesn't seem to have helped.

Heres my menu.lst

Code:

title		Ubuntu 8.04, kernel 2.6.24-16-generic
root		(hd0,0)
kernel		/boot/vmlinuz-2.6.24-16-generic root=UUID=074c9d6a-c235-4ef2-a129-b27316dd217d ro quiet splash
initrd		/boot/initrd.img-2.6.24-16-generic
quiet

title		Ubuntu 8.04, kernel 2.6.24-16-generic (recovery mode)
root		(hd0,0)
kernel		/boot/vmlinuz-2.6.24-16-generic root=UUID=074c9d6a-c235-4ef2-a129-b27316dd217d ro single
initrd		/boot/initrd.img-2.6.24-16-generic

title		Ubuntu 8.04, kernel 2.6.22-14-generic
root		(hd0,0)
kernel		/boot/vmlinuz-2.6.22-14-generic root=UUID=074c9d6a-c235-4ef2-a129-b27316dd217d ro quiet splash
initrd		/boot/initrd.img-2.6.22-14-generic
quiet

title		Ubuntu 8.04, kernel 2.6.22-14-generic (recovery mode)
root		(hd0,0)
kernel		/boot/vmlinuz-2.6.22-14-generic root=UUID=074c9d6a-c235-4ef2-a129-b27316dd217d ro single
initrd		/boot/initrd.img-2.6.22-14-generic

title		Ubuntu 8.04, memtest86+
root		(hd0,0)
kernel		/boot/memtest86+.bin
quiet

and my device.map

Code:

(hd0)	/dev/sda
(hd1)	/dev/sdb
(hd2)	/dev/sdc

syg00 · 03-04-2009, 03:53 PM

This should do it providing everything is in place.

Code:

root (hd0,0)
setup (hd0)

ilw · 03-04-2009, 04:04 PM

thanks for the quick response, but i tried that before and it didn't seem to do anything.

syg00 · 03-04-2009, 04:18 PM

You mentioned you'd done the "setup" command - you didn't mention that you'd done the "root" first.
Do you see the boot menu ?. If not, hit the <Esc> key when post finishes (i.e. the blank screen) within a few seconds. Then select the recovery option. Post any interesting messages.