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wombat53 09-02-2009 05:53 PM

Unable to boot into GRUB loader: GRUB command shell boots up: urgent issue
 
Hi - I have a (serious) problem, and help very greatly appreciated.
A failed upgrade, from disk images, of Fedora 10 to 11 resulted in no GRUB bootloader main menu appearing on bootup (no WIN, no LINUX choices from which to boot). I am booted directly into the GRUB command shell...so, no WIN, no LINUX, nothing. And my understanding of GRUB shell commands is very low.
I have 2 hard disks, WIN on the first, LINUX on the second. I believe GRUB Bootloader is on the first disk.
Sadly, I have no external install media.
An old grub.conf hardcopy indicates that root =/dev/sdb2, root (hd1,0), kernel /vmlinuz....olderversion...(relative to /boot),
initrd /initrd...olderversion... (relative to boot).
and WINDOWS on (hd0,1), with chainloader +1

I need to somehow get past this grub shell, and re-install/re-instate the grub bootloader, so it can boot normally.
What grub command(s) must I use? I've played around with the commands, but with no success.
I worry that if I can't resolve this, the whole machine may be useless.
I pray someone can help me here.
Thanks
George

Larry Webb 09-02-2009 07:55 PM

I am sure the machine can be saved, it is a matter of figuring out what happened. We need more information, was this upgrade from a cd, dvd, internet connection? How far did the upgrade get before stopping? Were there any error messages? If nothing else from the grub shell enter the following

grub>
title windows
rootnoverify (hd0,0)
chainloader +1
boot

This should get you back to windows if it is in the first partition of the first boot hd. If not we will need more information.

wombat53 09-02-2009 09:14 PM

Larry
Was upgrade from decompressed .iso image, using the "install.img" method.
Failed while writing partitions to disk using anaconda. No error message.
I honestly don't remember more....sorry.....
I have been told to do something like this....:
grub> find /vmlinuz ( from this result you should be able to insert hd?,? into the next line )
grub> where (hd?,?) vmlinuz <TAB> and it should list the filenames
find /boot/vmlinuz
grub> root (hd1,0)
grub> kernel /vmlinuz-(from command 2 above) root=/dev/sdb2
grub> boot

I may also need grub>initrd filename details before the final boot step.
Then I may have to re-install grub.

This is consistent with what I've read on the web, assuming I have the correct grub and Linux device names from an old hardcopy of my grub.conf files. Even if not, the various "find" commands should confirm I do have the correct kernel, initrd and device names. Having no google last nite, I didn't have access to info, nor people where I work.

Seem like a reasonable sequence?

George

Larry Webb 09-03-2009 06:56 AM

Did you try my entry for your windows install? It should be safe. Being honest I am not familiar with fedora. Seeing you do not have a disc, we are limited as to what we can do. Do you have an old fedora disc or any linux distro disc that can be run as live cd?

If not see if you can at least download a copy of 'Super Grub' and burn it to disc. It would be better if you could burn a distro live cd.

ronlau9 09-03-2009 07:14 AM

How did you upgrade to Fedora 11 ?
I mean did you do it in that way that the boot partition of Fedora 11 stay
/ = ext3 and the rest ext 4
My understanding is that GRUB can not read from ext4
It seems that LILO can

wombat53 09-03-2009 06:29 PM

Larry - I tried the WIN boot, with no success.
The Fedora installation was by the book, from the install image, per the Fedora project guidelines. I never requested any re-partitioning, but anaconda seemed to intervene anyway.

The grub commands below all failed...no files could be found (vmlinuz, initrd etc...); am presuming the LINUX disk was partitioned/reformatted before failing, and is useless. I can live with this.

Worse still, the grub bootloader (which resides on WIN disk), is clearly corrupted. I would like to restore the MBR of (WIN) disk 1, if possible. I understand there are commands to do this, tho' I don't have a floppy rescue disk at this moment. My work laptop has no floppy, but am trying to obtain one from am friend.
Re-boot from a Fedora 9 install DVD yielded kbrd error...strike F1 for...something, F2 for setup...all failed.
As I see it, I now need to do as above; try and re-create the WIN MBR to invoke the NT bootloader. Perhaps once I get WIN back, I can try and re-install LINUX.
George

Larry Webb 09-03-2009 07:16 PM

If you use a live cd from the terminal you can see what is left on your drive and see how it is partitioned. If you do not want to go this route, 'Super Grub' disc will boot windows also if there is a windows left to boot. Without more information I am afraid I can only recommend a clean install.

wombat53 09-04-2009 05:08 AM

I've managed to boot back to WINDOWs as follows (data from the old grub.conf file, as follows:
rootnoverify (hd0,0)
chainloader +1
boot

But I am sure if I reboot I'll get back to the grub command line shell. I' wish to now replace the grub bootloader (which I believe lives on the (first) hard drive, containing windows, with ther WIN NT bootloader.
Is there a way to do this?
Then I can think about re-installing LINUX. But at least I have WIN back, and my data is available.
Many thanks to Larry Webb.
Thanks
George

Larry Webb 09-04-2009 06:07 AM

I do not know enough, which version the 32 bit or 64 bit, which kernel, what partition number? If you have a dvd or cd I would recommend a new install or repair. Most of the new distros on dvd have a repair option which may get you back working. If cd then we can use as live and find the information we need.

wombat53 09-04-2009 06:20 AM

Larry - thanks to your suggestion re the GRUB prompt, I was able to boot WIN. Then I was able to put install CD (in DVD!) drive, and run FIXMBR, FIXBOOT, and now have removed grub bootloader, and WIN boots cleanly!!
So far, so good.
Now, back to Linux (a second disk (hd1) = dev/sdb.

I do have the following file:
Fedora-11-i386-DVD.iso all, 3.5GB of it, and so wish to re-install Linux on 2nd drive, WITHOUT LOGICAL VOLUMES, which I've always been able to do.
Unfortunalty anaconda reared its ugly head in the upgrade from 10 to 11 and trashed the LINUX partition, ging rise to these problem, most of which are fixed now.
I just want a simple system, with 3 partitions - as I have always had - /, /boot, and swap.
I think I also want the GRUB bootloader NOT to be on the WIN disk (MBR), but on the (Dedicated)LINUX disk
George


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