Strong problem with GRUB (almost solved)

destroyedlolo

Hello,

On my main machine, I had the following setup.

----
IDE :
sda1 : 320 GB data
sda2 : 15 MB Gentoo boot

sdb1 : 40 GB Ubuntu
sdb2 : 1.5 GB swap

SCSI :

sdc1 : 15 MB Gentoo boot
sdc2 : 18 GB Gentoo
sdc3 : 22 GB data

---

sdb is the disk used to boot, using Ubuntu Grub2 with a multi boot. Unfortunately, this disk corrupts it's data in case of power faillure and last time, corrupted even Grub.
After booting with Ubuntu liveCD, I was able to do a chkfs and was able to boot again on Ubuntu ... but grub failled to boot Gentoo saying it can't find sdc1 disk by it's UUID.

I wasn't able to re-install Grub as my Ubuntu was deprecated so I decided to upgrade to the LTS ...

Reboot and ... now it is not anymore to boot :

booting on Ubuntu (so /sdb1) :

Quote:

mount : mounting /dev/disk/by-uuid/6493890... on /root failled : invalid argument
booting on Gentoo (/sdc2)

Quote:

error : no such device hd2,1 cannot get C/H/S value

Unfortunately, my scsi controler can't boot, so using Gparted, I created /sda2 and copy /sdc2 on it (Gentoo boot partition).
From Gentoo install CD, I chrooted on Gentoo and tried to install GRUB on (hd0) but boot is failling as well

with
Code:

root (hd0,1)
(so /sda2) -> Error 17
with
Code:

root (hd2,0)
(so /sdc1) -> Error 21

I tried everything I found on the net w/o success :

Code:

find /boot/grub/stage1
displays both (hd0,1) and (hd2,0) so I think the path is correct
as per fdisk, partitions are in the correct orders on all disks ...

I really don't know to do now ???? I'm lost (and I hate Grub :evil:

).
Any help greatly appreciated.

Laurent

Dont Panic · Posted: Mon Apr 23, 2012 9:18 pm Post subject: Re: Strong problem with GRUB

destroyedlolo · Posted: Mon Apr 23, 2012 10:35 pm Post subject:

unfortunately, no because it's Grub1 I installed on Gentoo

So those numbers reflect my partitions.

Dont Panic · Posted: Mon Apr 23, 2012 11:06 pm Post subject:

It might be worthwhile to confirm that grub is seeing your partition order in the same way as fdisk.

When you get your Grub1 menu during boot, hit the "c" key. This will give you a command menu.

Run:

destroyedlolo · Posted: Tue Apr 24, 2012 4:58 pm Post subject:

Dont Panic · Posted: Tue Apr 24, 2012 6:59 pm Post subject:

destroyedlolo · Posted: Tue Apr 24, 2012 8:32 pm Post subject:

Dont Panic · Posted: Wed Apr 25, 2012 1:25 am Post subject:

Let me paraphrase my understanding of Grub errors 17 and 21, and tell me if you are seeing anthing different.

Grub1 Error 17: Grub sees the partition, and it looks like Grub should know what to do with that partition, but Grub isn't able to find what it expects to find on that partition.

Grub1 Error 21: Grub is having a problem doing anything with the partition.

A common attempt to fix Error 17 would be to reinstall Grub.

A common fix for Error 21 involves finding a boot partition on another drive, and setting up your kernel and initramfs there.

Here's a couple of things you could try (they're not in order, and are all separate ideas):
(1) Double check and make sure /boot/<kernel-name> is what you want. When Grub looks at your boot partition, it doesn't know it was mounted /boot/ on your installed system. It sees everything as /. There should probably be a symlink pointing /boot to the main directory. Either that, or just drop the '/boot' portion of your kernel names.

(2) Reinstall Grub1

(3) Make a directory on your Ubuntu partion (such as /boot/gentoo), and place your kernel there. Then make a Grub entry for that kernel.

Basically, you would be using some of the space on your Ubuntu partion to act as a really big /boot directory. It won't really interfere with anything on Ubuntu. I suggest this since that is the only partition you have marked as 'bootable' in fdisk.

(4) Make an initramfs for your kernel, and include that in your Grub configuration. Unfortunately, you have really small boot partitions. And, the Error 17 makes me think Grub is still having trouble even reading your boot partitions.

destroyedlolo · Posted: Wed Apr 25, 2012 1:01 pm Post subject:

destroyedlolo · Posted: Wed Apr 25, 2012 6:58 pm Post subject:

Reseting the BIOS did help :evil:

I read that some BIOS can't boot from partition far in the HD ... so I'll move my boot partition to the begining of the disk ...

destroyedlolo · Posted: Wed Apr 25, 2012 10:51 pm Post subject:

Well, I'm now able to boot on Gentoo

I re-formated my /sda (320 GB), but my boot partition at the beginning (hd0,0), rerun grub ... and now I'm able to boot. Consequently, I totally removed the Maxtor disk that create nightmare everytime the machine is suffering for power outage.

Now :

I have to add Ubuntu into HD0 grub ... not an issue.
Ubuntu's Grub on HD1 is totally messed up and not able to boot on my SCSI drive : same messages about C/H/S. I don't care, as I'll not use it anymore as soon as Ubuntu is added in HD0 one.
My Ubuntu is still suffering for problem (mount message at boot up), but I don't really care as my main OS is Gentoo.

It seems that Grub really rely on the Bios and my Bios is too old (2000 !) to handle boot partition far in disk space ...

Dont Panic · Posted: Thu Apr 26, 2012 4:40 am Post subject:

Awesome! Congratulations!

You may still be able to host a root partition on your SCSI drive, but you would have to boot with a kernel and initramfs on the drive that Grub recognizes.

destroyedlolo · Posted: Sat May 05, 2012 9:57 am Post subject:

If it can help someone, I've been able also to chain to hd1's Ubuntu grub2 by adding following lines ...