Stuck at grub prompt after upgrade from 9.10 -> 10.04

[ChaozUT]

Background:

After upgrading from Ubuntu 9.10 to 10.04 via the update manager, I was stuck at grub rescue prompt after rebooting. After trying the GRUB repair utility I can now boot to a grub> prompt but no further.

I was not the original person who set this machine up. On this machine there are six 1.5TB drives, sda through sdf, with two partitions each. The first partition is 1GB (ex. sda1) and the second is the rest of the drive (ex. sda2)
- sda1 to sde1 is in a 5 drive RAID5 config to make 4GB of what I think is swap space (md126)
- sda2 to sdf2 is in a 6 drive RAID5 config to form one big ~7.5TB drive (md127)
- sdf1 is a single 1GB partition which seems to be for booting purposes.

Problem:

- First of all, I am now stuck at the grub> prompt when trying to boot.
- When I type "boot" it says something along the lines of "kernel not set".
- When I type "set" it shows a bunch of config data, but mainly it shows that the root is (md127), the big 7.5TB drive, and that the prefix is (md127)/boot/grub/

What is confusing me and I think that this may be the source of the problem is that both md127 and sdf1 have grub folders on them. Also, it seems like each has only part of the files. I have listed out an overview of the directory listing for these two drives to show what I mean by this. Hopefully, whoever looks at this will be able to see what needs to be done. I have some suspicions but would rather not act on them yet without some guidance since I am not a linux expert. Here is the listing:

BLUE = Directory
GREEN = File
Black = Comment



/md127/: (7.5TB RAID5)
- /boot/

- /grub/


- /locale/



- en_AU.mo



- en_CA.mo



- en_GB.mo


- fs.list


- grub.cfg


- grubenv


- <other misc .mod .img .lst files, except no menu.lst>

- <nothing else>
- initrd.img (symbolic link to boot/initrd.img-2.6.32-35-generic, which DOES NOT EXIST on this drive)
- initrd.img.old (symbolic link to boot/initrd.img-2.6.31-19-generic, which DOES NOT EXIST on this drive)
- vmlinuz (same thing as above, symbolic link to something that does not exist)
- vmlinuz.old
- <system folders such as dev, home, usr, var, etc.>


/sdf1/: (1GB single partition)
- /boot/

- /grub/


- <seems to have everything except grub.cfg and menu.lst>

- <nothing else>
- /grub/

- <seems to have everything except menu.list>
- <bunch of abi-... with latest being abi-2.6.32-35-generic>
- <bunch of config-... with latest being config-2.6.32-35-generic>
- <bunch of initrd... with latest being initrd.img-2.6.32-35-generic>
- <bunch of System.map... with latest being System.map-2.6.32-35-generic>
- <bunch of vmcoreinfo... with latest being vmcoreinfo-2.6.32-35-generic>
- <bunch of vmlinuz... with latest being vmlinuz-2.6.32-35-generic>
- memtest86+.bin


Just from the above I am not sure which files are needed where for the boot to be successful. It seems that md127 contains initrd and vmlinuz symbolic links that point to files that do not exist on md127 (but does exist on sdf1). But at the same time, there are 2 grub folders on sdf1 (/boot/grub and /grub) and one of them is missing a grub.cfg file.

Any advice on how to proceed would be greatly greatly appreciated. :confused:

[Rubi1200]

Hi and welcome to the forums :-)

Thanks for supplying us with as much information as possible as it really helps us.

One more thing we need right now is to see the results of the boot info script.

There is a link at the bottom of my post with instructions.

Thanks.

[ChaozUT]

The boot_info_script output is below. One additional thing to note is that I just realized that the RAID5 (md127) partition that I reassembled is stuck in read-only mode, and auto mounts after I dismount it. I am not sure if this would have caused by problem (or perhaps cause a different problem down the line once it boots...). I am currently running the RAID repair utility on the 10.04 liveCD.

EDIT: ignore sdg. That is an external hard drive I plugged in.


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 for (md127)/boot/grub on this drive.
=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sdb and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks for (md127)/boot/grub on this drive.
=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sdc and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks for (md127)/boot/grub on this drive.
=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sdd and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks for (md127)/boot/grub on this drive.
=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sde and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks for (md127)/boot/grub on this drive.
=> Grub2 (v1.97-1.98) is installed in the MBR of /dev/sdf and looks at sector
1 of the same hard drive for core.img. core.img is at this location and
looks for (md127)/boot/grub on this drive.
=> No boot loader is installed in the MBR of /dev/sdg.

sda1: __________________________________________________ ________________________

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

sda2: __________________________________________________ ________________________

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

sdb1: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdb2: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdc1: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdc2: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdd1: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdd2: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sde1: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sde2: __________________________________________________ ________________________

File system: linux_raid_member
Boot sector type: Unknown
Boot sector info:

sdf1: __________________________________________________ ________________________

File system: ext4
Boot sector type: Grub2 (v1.97-1.98)
Boot sector info: Grub2 (v1.97-1.98) is installed in the boot sector of
sdf1 and looks at sector 392063 of the same hard drive
for core.img. core.img is at this location and looks
in partition 1 for /grub.
Operating System:
Boot files: /grub/grub.cfg /grub/core.img /boot/grub/core.img

sdf2: __________________________________________________ ________________________

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

sdg1: __________________________________________________ ________________________

File system: ntfs
Boot sector type: Windows XP
Boot sector info: No errors found in the Boot Parameter Block.
Operating System:
Boot files:

md126: __________________________________________________ _______________________

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

md127: __________________________________________________ _______________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 10.04.3 LTS
Boot files: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img

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

Drive: sda __________________________________________________ ___________________

Disk /dev/sda: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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 * 63 1,959,929 1,959,867 fd Linux raid autodetect
/dev/sda2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sdb __________________________________________________ ___________________

Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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/sdb1 * 63 1,959,929 1,959,867 fd Linux raid autodetect
/dev/sdb2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sdc __________________________________________________ ___________________

Disk /dev/sdc: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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/sdc1 63 1,959,929 1,959,867 fd Linux raid autodetect
/dev/sdc2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sdd __________________________________________________ ___________________

Disk /dev/sdd: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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/sdd1 63 1,959,929 1,959,867 fd Linux raid autodetect
/dev/sdd2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sde __________________________________________________ ___________________

Disk /dev/sde: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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/sde1 63 1,959,929 1,959,867 fd Linux raid autodetect
/dev/sde2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sdf __________________________________________________ ___________________

Disk /dev/sdf: 1500.3 GB, 1500301910016 bytes
255 heads, 63 sectors/track, 182401 cylinders, total 2930277168 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/sdf1 * 63 1,959,929 1,959,867 83 Linux
/dev/sdf2 1,959,930 2,930,272,064 2,928,312,135 fd Linux raid autodetect


Drive: sdg __________________________________________________ ___________________

Disk /dev/sdg: 1500.3 GB, 1500301910016 bytes
1 heads, 63 sectors/track, 46512336 cylinders, total 2930277168 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/sdg1 63 2,930,272,127 2,930,272,065 7 NTFS / exFAT / HPFS


"blkid" output: __________________________________________________ ______________

Device UUID TYPE LABEL

/dev/loop0 squashfs
/dev/md126 73f979af-ab81-4385-9876-cda06ff85a46 swap
/dev/md127 fbafc46f-7238-4af5-a6e7-e9241e3acc4f ext4 bigdrive
/dev/sda1 3444b803-6d39-fac1-486d-98e3a3ed0bff linux_raid_member
/dev/sda2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sdb1 3444b803-6d39-fac1-486d-98e3a3ed0bff linux_raid_member
/dev/sdb2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sdc1 3444b803-6d39-fac1-486d-98e3a3ed0bff linux_raid_member
/dev/sdc2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sdd1 3444b803-6d39-fac1-486d-98e3a3ed0bff linux_raid_member
/dev/sdd2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sde1 3444b803-6d39-fac1-486d-98e3a3ed0bff linux_raid_member
/dev/sde2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sdf1 b081ffab-a0db-4d17-969b-a8ac4899ec3b ext4
/dev/sdf2 15135403-8c15-00bd-4955-6804d345d67a linux_raid_member
/dev/sdg1 1A20A39D20A37DFF ntfs Expansion Drive

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

Device Mount_Point Type Options

/dev/loop0 /rofs squashfs (ro,noatime)
/dev/md127 /media/bigdrive ext4 (rw,nosuid,nodev,uhelper=udisks)
/dev/sdf1 /media/b081ffab-a0db-4d17-969b-a8ac4899ec3b ext4 (rw,nosuid,nodev,uhelper=udisks)
/dev/sdg1 /media/Expansion Drive fuseblk (rw,nosuid,nodev,allow_other,blksize=4096,default_ permissions)
/dev/sr0 /cdrom iso9660 (ro,noatime)


============================= sdf1/grub/grub.cfg: ==============================