Friday, December 28, 2012

three computers running openSUSE with broken GRUB configurations

I.e. they don't start beyond the GRUB boot loader.

So far I had only known of 2 computers, my non-portable ones at home, and because of that, I actually had no computer for weeks to reach through my DynDNS host name. That was already rather bad. So far I actually thought, I had described this problem already properly under the grub label on this blog.

I actually had not known until this morning, that my ASUS portable PC also suffers from a GRUB configuration problem. This is terrible. I had planned to boot it, so I could work on some 1st block of book keeping. I am a little desperate. Instead of book keeping I have to work on fixing operating system problems.

My only running openSUSE Linux is the respective VM on my MacBook Pro. I must be brave now, and try to fix one GRUB problem after the other. Maybe one or two recipes will work for all three. My ASUS portable PC GRUB problem reads like this:
kernel …
Error 15: File not found
Press any key to continue…
Well, there are not that many items, GRUB may regard as file. It's either the file holding the bootable kernel, or it's the root partition.  Well, yes, the root partition isn't really a file, but then the term may just be used a little unprecise.

I first tried to fix the GRUB configuration. I found, that the GRUB menu now shows GRUB (let's call them "GRUB1") and GRUB2 entries. I didn't manage to fix either of them.

Then I tried to "update-install" the operating system. At worst I would uninstall the GRUB1 and also the GRUB2 packages, maybe even remove the /boot directory, and start with an "old-fashioned" GRUB1 configuration.

 I booted from the resp. DVD, and updated the OS over the Internet. As usual you are getting far more packages updated, than you need in such a situation, and the announcement said, it would take like 75 minutes. Terrible. Looks though, as it's going to be faster. Yes, it went faster.

When I rebooted (through the DVD) from the hard disk, the GRUB2 entry had gotten removed, but still "Error 15: File not found". Both the kernel file and the initrd file names had not gotten updated to the right names of the most-up-to-date and installed files (the openSUSE GRUB updater scripts were quite able to deal with that in the past). Fixing that manually only took a finger snapping. I was in shock: yes, the OS would boot.

For the time being I will seriously avoid using GRUB2. I assume that saves me trouble.

Looks like running grub-install as root is quite helpful.

Would there be yet another obstacle? Looks like there is none (for the time being). So "in the background" I will try fixing the other 2 stuck computers like this as well.

1of2 had a /boot/grub/menu.lst, that was broken, but I could easily fix it "on the fly" within GRUB, after GRUB stopped because of one of these errrors. Then I started "yast2 bootloader", and did the lasting fix.

2of2 had no useful /boot/grub/menu.lst at all. I booted from the DVD into the rescue system. I copied a somehow reasonable menu.lst from another computer via a USB memory stick to this system, rebooted, and fixed it "on the fly" as well, so that I could properly boot into a running system. There again I started "yast2 bootloader", and did the lasting fix.

Everything is fixed now.

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