Grub Rescue Prompt on Kubuntu 10.04 LTS

[jal492]

I'm having major headaches with Grub 2 on a Seagate ST310005 28as 1TB SATA drive in an external HD enclosure. I'm trying to boot via USB, but all I get is the grub rescue> prompt.

I know the BIOS is set to boot from a USB-HD, and is set at the highest boot priority.

This drive was previously installed in my desktop machine, connected with the SATA cable, where it wouldn't boot on the first attempt but would always successfully boot on the second go (after Ctrl-Alt-Del at grub rescue>).

I've tried using Gparted Live to check for problems - no joy there, as it can't see the main primary bootable partition. (Oddly, it finds the swap partition OK.)

I have also checked out the Kubuntu and Ubuntu forums for people having similar problems, and tried manually doing "set prefix=...", "set root=...", etc. at the rescue> prompt but Grub returns either "out of disc" or "not found"-type errors.

I did manage to run boot_info_script the last time I was able to boot the drive while it was in my desktop; however, I've since moved and no longer have this available (hence putting it into the external HD enclosure).


Could this be a partitioning issue? Or is it Grub 2? Or the fact that I'm trying to use USB rather than SATA or eSATA? Given that I can't boot to edit the grub config files or run grub-update, how can I solve this? I have the original Kubuntu 10.04 LTS installation disc, but I think it's the 'Alternate' version - not the 'Live' version...

This was a totally new, clean drive before I installed Kubuntu on it, and having used 8.04 for years without problems, I'm really disappointed that 10.04 seems to be throwing up so many issues for so many people.
I have a ton of files on this drive I need to access for Uni - anyone have any idea what I could try next?


Sincere Thanks in Advance!



Output from boot_info_script:



Boot Info Script 0.60 from 17 May 2011


============================= Boot Info Summary: ===============================

=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sda and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks in partition 1 for /boot/grub.

sda1: __________________________________________________ ________________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 10.04.2 LTS
Boot files: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img

sda2: __________________________________________________ ________________________

File system: Extended Partition
Boot sector type: -
Boot sector info:

sda5: __________________________________________________ ________________________

File system: swap
Boot sector type: -
Boot sector info:

============================ Drive/Partition Info: =============================

Drive: sda __________________________________________________ ___________________

Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes

Partition Boot Start Sector End Sector # of Sectors Id System

/dev/sda1 * 2,048 1,947,510,783 1,947,508,736 83 Linux
/dev/sda2 1,947,512,830 1,953,523,711 6,010,882 5 Extended
/dev/sda5 1,947,512,832 1,953,523,711 6,010,880 82 Linux swap / Solaris


"blkid" output: __________________________________________________ ______________

Device UUID TYPE LABEL

/dev/sda1 e87c9cdd-8ca4-44b3-8049-2c2591120c5b ext4 linux
/dev/sda5 a2ec9eb0-b4d6-459e-be60-52acd8525bd3 swap

================================ Mount points: =================================

Device Mount_Point Type Options

/dev/sda1 / ext4 (rw,errors=remount-ro)


=========================== sda1/boot/grub/grub.cfg: ===========================

--------------------------------------------------------------------------------
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by /usr/sbin/grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
load_env
fi
set default="0"
if [ ${prev_saved_entry} ]; then
set saved_entry=${prev_saved_entry}
save_env saved_entry
set prev_saved_entry=
save_env prev_saved_entry
set boot_once=true
fi

function savedefault {
if [ -z ${boot_once} ]; then
saved_entry=${chosen}
save_env saved_entry
fi
}

function recordfail {
set recordfail=1
if [ -n ${have_grubenv} ]; then if [ -z ${boot_once} ]; then save_env recordfail; fi; fi
}
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
if loadfont /usr/share/grub/unicode.pf2 ; then
set gfxmode=640x480
insmod gfxterm
insmod vbe
if terminal_output gfxterm ; then true ; else
# For backward compatibility with versions of terminal.mod that don't
# understand terminal_output
terminal gfxterm
fi
fi
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
set locale_dir=($root)/boot/grub/locale
set lang=en
insmod gettext
if [ ${recordfail} = 1 ]; then
set timeout=-1
else
set timeout=10
fi
### END /etc/grub.d/00_header ###

### BEGIN /etc/grub.d/05_debian_theme ###
set menu_color_normal=white/black
set menu_color_highlight=black/light-gray
### END /etc/grub.d/05_debian_theme ###

### BEGIN /etc/grub.d/10_linux ###
menuentry 'Ubuntu, with Linux 2.6.32-32-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
linux /boot/vmlinuz-2.6.32-32-generic root=UUID=e87c9cdd-8ca4-44b3-8049-2c2591120c5b ro quiet splash
initrd /boot/initrd.img-2.6.32-32-generic
}
menuentry 'Ubuntu, with Linux 2.6.32-32-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
echo 'Loading Linux 2.6.32-32-generic ...'
linux /boot/vmlinuz-2.6.32-32-generic root=UUID=e87c9cdd-8ca4-44b3-8049-2c2591120c5b ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.32-32-generic
}
menuentry 'Ubuntu, with Linux 2.6.32-21-generic' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
linux /boot/vmlinuz-2.6.32-21-generic root=UUID=e87c9cdd-8ca4-44b3-8049-2c2591120c5b ro quiet splash
initrd /boot/initrd.img-2.6.32-21-generic
}
menuentry 'Ubuntu, with Linux 2.6.32-21-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os {
recordfail
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
echo 'Loading Linux 2.6.32-21-generic ...'
linux /boot/vmlinuz-2.6.32-21-generic root=UUID=e87c9cdd-8ca4-44b3-8049-2c2591120c5b ro single
echo 'Loading initial ramdisk ...'
initrd /boot/initrd.img-2.6.32-21-generic
}
### END /etc/grub.d/10_linux ###

### BEGIN /etc/grub.d/20_memtest86+ ###
menuentry "Memory test (memtest86+)" {
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
linux16 /boot/memtest86+.bin
}
menuentry "Memory test (memtest86+, serial console 115200)" {
insmod ext2
set root='(hd0,1)'
search --no-floppy --fs-uuid --set e87c9cdd-8ca4-44b3-8049-2c2591120c5b
linux16 /boot/memtest86+.bin console=ttyS0,115200n8
}
### END /etc/grub.d/20_memtest86+ ###

### BEGIN /etc/grub.d/30_os-prober ###
if [ ${timeout} != -1 ]; then
if keystatus; then
if keystatus --shift; then
set timeout=-1
else
set timeout=0
fi
else
if sleep --interruptible 3 ; then
set timeout=0
fi
fi
fi
### END /etc/grub.d/30_os-prober ###

### BEGIN /etc/grub.d/40_custom ###
# This file provides an easy way to add custom menu entries. Simply type the
# menu entries you want to add after this comment. Be careful not to change
# the 'exec tail' line above.
### END /etc/grub.d/40_custom ###
--------------------------------------------------------------------------------

=============================== sda1/etc/fstab: ================================

--------------------------------------------------------------------------------
# /etc/fstab: static file system information.
#
# Use 'blkid -o value -s UUID' to print the universally unique identifier
# for a device; this may be used with UUID= as a more robust way to name
# devices that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
# / was on /dev/sda1 during installation
UUID=e87c9cdd-8ca4-44b3-8049-2c2591120c5b / ext4 errors=remount-ro 0 1
# swap was on /dev/sda5 during installation
UUID=a2ec9eb0-b4d6-459e-be60-52acd8525bd3 none swap sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0 0
--------------------------------------------------------------------------------

=================== sda1: Location of files loaded by Grub: ====================

GiB - GB File Fragment(s)

722.138877869 = 775.390715904 boot/grub/core.img 1
668.225788116 = 717.501976576 boot/grub/grub.cfg 1
722.146602631 = 775.399010304 boot/initrd.img-2.6.32-21-generic 1
722.273490906 = 775.535255552 boot/initrd.img-2.6.32-32-generic 1
722.129730225 = 775.380893696 boot/vmlinuz-2.6.32-21-generic 1
722.136573792 = 775.388241920 boot/vmlinuz-2.6.32-32-generic 1
722.273490906 = 775.535255552 initrd.img 1
722.146602631 = 775.399010304 initrd.img.old 1
722.136573792 = 775.388241920 vmlinuz 1
722.129730225 = 775.380893696 vmlinuz.old 1

[raja.genupula]

HI man you can get your GRUB back.

look at my signture for GRUB 2 and Grub Recovery .I am sure they gonna help you to solve your issue.

[jal492]

Thanks for taking the time to help me out Raja :)

OK, I tried using the 'Alternate' CD method mentioned in the https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows link in your signature; however, when it comes time to choose the partition, my main primary partition isn't there, so I can't go any further.

I will try researching the Grub 2 commands as noted in the other link more thoroughly to see if there's anything else I can try.

Oh, and I meant to add that Grub 2 was also throwing up "unknown filesystem" errors at the rescue prompt - seems it can see my drive and partitions, but can't read the filesystem (which is ext4).

Beginning to think this might not be just one issue, but many... Also that ext4 was an unwise choice for a filesystem - a total lemon, in fact. But then, it was the default option when I installed, so I (naively) assumed that it would be fine. How wrong I was!

[jal492]

OK, tried playing around with the set prefix=... and set root=... but after that, I can't go any further.

I booted to a shell via the Kubuntu 10.04 LTS 'Alternate' disc and tried to see if I could find anything that might be useful. (I had to select 'no root filesystem' - as I mentioned before, the main primary partition isn't listed as an option.)

Output from sfdisk would seem to indicate that the drive's partition table is incorrectly set up, but I don't have a clue as to whether this can be fixed, and whether my problem is due to this or something else...

Output from sfdisk:


# sfdisk -l /dev/sdc

Disk /dev/sdc: 1017 cylinders, 2 heads, 32 sectors/track
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
lseek: Invalid argument

sfdisk: seek error on /dev/sdc - cannot seek to 1947512830
Warning: The partition table looks like it was made
for C/H/S=*/255/63 (instead of 1017/2/32).
For this listing I'll assume that geometry.
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/sdc1 * 0+ 121226- 121227- 973754368 83 Linux
/dev/sdc2 121227+ 121601- 375- 3005441 5 Extended
/dev/sdc3 0 - 0 0 Empty
/dev/sdc4 0 - 0 0 EmptyShould I be concerned about this?

Not sure what else to try...

[jal492]

Further info I've been able to discover:

Using fixparts from a handy bootable Slax USB key:


FixParts 0.8.0

Loading MBR data from /dev/sdd
Unable to seek to 1947512830! Aborting!
MBR signature in logical partition invalid; read 0x0820, but should be 0xAA55
Segmentation fault



and see the attached .jpeg for some baffling stuff, using a bootable Gparted-live-0.6.1-2 disc.

Anybody?

:confused: