Linux Mint Broke Ubuntu Boot

[majgeek]

Have a dual boot set up with two hard disks , and I have Ubuntu 10.10 installed on one hard disk, and installed Mint 10 on the other. After installing Mint, Ubuntu will no longer boot properly. Ubuntu always boots into the recovery console. I can drop to the command line and login as root or with my user account and start x server, and it loads up fine, and I can access my files (Except not everything works quite right. e.g. can't connect to the internet unless I by pass my router. (DHCP is not working) and some utilities don't work right.

I thought Mint might have done something to grub so I fiddled around with it, and eventually purged grub and reinstalled. No joy. I checked the drives for errors. No joy there either. Mint loads fine, Ubuntu still won't boot. I disconnected the hard drive with Mint on it, and booted to the old grub from my Ubuntu install. Still the same problem.

What could have happened?

[seeley]

Hi majgeek!
Please read my help (link below) and post the output of Terminal -> II, G and P.
seeley

[majgeek]

Description: Linux Mint 10 Julia
Linux Minty-Box 2.6.35-22-generic-pae #35-Ubuntu SMP Sat Oct 16 22:16:51 UTC 2010 i686 GNU/Linux
HDD Total Size: 320.1GB (8.3% used) 1: /dev/sda ST3160815AS 160.0GB
gnome ver. 2.32.0

________________________________________________________________________

/dev/sda: GRUB 2 v1.97 or higher
/dev/sdb: GRUB 2 v1.97 or higher

_________________________________________________________________________

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x4b41bda6

Device Boot Start End Blocks Id System
/dev/sda1 * 1 1958 15727603+ 7 HPFS/NTFS
/dev/sda2 1959 19457 140560687 f W95 Ext'd (LBA)
/dev/sda5 1959 2611 5245191 b W95 FAT32
/dev/sda6 2612 18768 129781071 83 Linux
/dev/sda7 18769 19457 5534361 82 Linux swap / Solaris

Disk /dev/sdb: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x88d588d5

Device Boot Start End Blocks Id System
/dev/sdb1 1 729 5855630+ 5 Extended
/dev/sdb2 * 4570 7833 26218080 7 HPFS/NTFS
/dev/sdb3 7834 19457 93369780 7 HPFS/NTFS
/dev/sdb4 730 4569 30844800 83 Linux
/dev/sdb5 1 729 5855629+ 82 Linux swap / Solaris

Partition table entries are not in disk order

___________________________________________________________________________

Model: ATA ST3160815AS (scsi)
Disk /dev/sda: 160GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 32.3kB 16.1GB 16.1GB primary ntfs boot
2 16.1GB 160GB 144GB extended lba
5 16.1GB 21.5GB 5371MB logical fat32
6 21.5GB 154GB 133GB logical ext4
7 154GB 160GB 5667MB logical linux-swap(v1)


Model: ATA ST3160811AS (scsi)
Disk /dev/sdb: 160GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 63.5kB 5996MB 5996MB extended
5 64.5kB 5996MB 5996MB logical linux-swap(v1)
4 5996MB 37.6GB 31.6GB primary ext4
2 37.6GB 64.4GB 26.8GB primary ntfs boot
3 64.4GB 160GB 95.6GB primary ntfs


Warning: Unable to open /dev/fd0 read-write (Read-only file system). /dev/fd0
has been opened read-only.

I don't understand that very last warning or error about /dev/fd0. What device is that? I have no floppy drive, or flash drives plugged in.

[seeley]

Hi majgeek!
One hard disk is internal and one external?
You first installed Ubuntu and then Mint - do you remember: where did you install the Mint Grub?
You have both live mediums (Ubuntu live and Mint live: CD / DVD) you used to install?
Sometimes installing Grub fails (no one knows why), so it is necessary to repair Grub.
Did you save all important data?
Then I suggest first to try to repair the Ubuntu Grub (therefore you need the live medium you used to install Ubuntu).
seeley

Edit:
You can ignore the warning (bug?)

[majgeek]

One hard disk is internal and one external?

No both hard disks are internal SATA's. It has been my practice for a long time to have two linux installs, as well as a Windows install. When a new version of Mint or Ubuntu comes out I install over the older of the two, (always reformat and fresh install) while keeping my main install until I get the other one all set up the way I want. Plus this always gives me a backup. I have done this back and forth install method many times without so much as a hiccup. I don't know what happened this time.

You first installed Ubuntu and then Mint - do you remember: where did you install the Mint Grub?

I installed grub to where ever the Mint installer chose by default. Which I believe would be the MBR of the drive it is installed on.

I already tried the live cd and reinstalling grub. I tried several different methods I found online. One thing I am not sure of is where is best to install grub. To the first track of the partition where linux is installed, or to MBR?

[seeley]

Hi majgeek!
First I must say, I don't have experience with 2 internal hard disks.
Normally - when I was installing a dual or tripel boot: the Grub of the first Linux I installed into the MBR (I selected a distri with GRUB"2" like Ubuntu, Sabayon or Mint), the Grub of the second Linux I installed into the root partition of Linux2 (one hd); afterwards an REBOOT and

Code: Select all

sudo update-grub

on Linux1 Desktop / Terminal found Linux1 (except PCLinuxOS) and after REBOOT the GRUB"2" menu showed all distris - to boot.
Your outputs are showing that both Grubs had been installed into a MBR - that could be the problem The second should have been installed into the first partition of the second hd - as I wrote: no experience with 2 hds.
My day is ending and I suggest we continue tomorrow.
seeley

[seeley]

Hi!
Did you modify the boot order to boot from sda as well as sdb; you got different error messages?
seeley

[wayne128]

I think you need to check the grub2 config files ( /boot/grub/grub.cfg) and see if anything amiss.
As you have two bootable partitions, two MBRs (two hard drives), so you need to check both files to ensure there are good.

It is also a good practice to save a good working grub cfg file. At situation like that, you can refer to the old working file with the new one ( created by Mint installation), then analyse the differences.
Often you could just replace the new file with the old working file in order to return to older boot instruction.

[wayne128]

One thing I am not sure of is where is best to install grub. To the first track of the partition where linux is installed, or to MBR?

For me I used this method:

1. I choose a Linux OS that acts also as "Master Boot Loader".
In this aspect I use grub legacy as master boot loader, then only the master boot loader control the MBR.
So I install this Linux OS and write boot code to MBR

2. The rest of the partitions, I used whatever its own default boot loader ( can be window's ntldr, Lilo, grub legacy, grub2,,) I would select to write boot code to the partition, or PBR (partition boot record).

Then I can be in control on MBR and the menu.lst which has grub instruction to boot all partitions.

When there is a boot problem, I check menu.lst and repair MBR or PBR.

[seeley]

Hi!

It has been my practice for a long time to have two linux installs, as well as a Windows install.

Which systems did you install on which hd?
To repair GRUB"2": Did you try the method "grub-setup"?
See here:
http://forums.linuxmint.com/viewtopic.p ... 28#p366328
G/ To repair GRUB"2"!
You still have your Ubuntu live medium to repair Grub?
seeley

[majgeek]

I finally managed to fix the problem.

I gleaned a few details from various sources around the web and then did the following ..

First I uplugged the hard disk with Mint installed on it to take that variable out of the picture. Then I booted from the Ubuntu LiveCD, and mounted my ubuntu install partition. Next I used this command to mount the necessary items for a Chroot from the LiveCD to the real system.

Code: Select all

 for i in /dev /dev/pts /proc /sys; do sudo mount -B $i /mnt/temp$i;  done

Next I use this ...

Code: Select all

chroot /mnt

to mount my ubuntu partition as active root. Then I used apt-get to purge grub, grub-pc, & grub-common and then reinstalled grub.

A quick reboot, and Viola! Ubuntu was smiling back at me.

Originally I tried purging and reinstalling grub after booting to root from the recovery console. I am not sure why it did not work that time around. Perhaps I missed something along the way.

[seeley]

Hi majgeek!
Glad to read that!
If you don't have further questions, please add [solved] to the subject line of your first posting.
seeley