kernel panic after adept upgrade

[Liam]

I have had linux up and running for a few months on this machine. I originally installed drapper off a CD a friend gave me.

Having done the last adept upgrade my machine worked fine until I rebooted it. Now I get the error message on boot "kernel panic - not syncing : VFS : unable to mount root fs on unknown block (0,0)"

I can get this machine to reboot by boot on the ver first kernel shown in the list (version 2.6.15.19-386) but it will not reboot on any of the later kernels listed at the boot option screen.

Latest boot option is 2.6.15.26.386

When I boot on 2.6.15.19-386 and do an adept update it retrieves the updates but after 3% of the update the update fails and I get an error message saying unable to complet update.

Any help would be greatly appreciated.

The machine has an AMD 1Ghz processor and a single 4Ghz harddrive. (plan is to run OS on this harddrive and install another hard drive for file storage, etc).

Please let me know what else you might need to know about this machine to assist me. Thanks heaps in advance for your help.

[askrieger]

Re: kernel panic after adept upgrade

Something doesn't add up. You say you "installed Dapper off a CD a friend gave me". You also say that you've had linux "up and running for a few months". But Dapper (Ubuntu 6-06) only came out in June. Two months could be considered a few, but then you also say that the only kernel that works for you is 2.6.15.19-386. The Dapper kernel on the CD is 2.6.15-23 (since updated by security to 2.6.15-26). I don't know which kernels were on the Dapper pre-release iso's, so it's possible that you're running one of those. I also don't remember which kernels were available for Breezy, so it's possible that you're running a Breezy kernel.

The message that you're getting indicates that the kernel was unable to find the root(/) file system. There are two possibilities (neither of which explains why 2.6.15-19 works and later kernels don't). It could be, for example if you're dual booting, that hda1 (0,0 in Grub speak) is NOT your root partition. It could also be that you're using ReiserFS, which people seem to be having problems with. Most likely, however, it's something that I haven't thought of.

The first thing I would do is correct your /boot/grub/menu.lst file if hda1 is not your root partition. The first number refers to the drive 0=a, 1=b, etc. The second number is the partition# minus 1. If that's not your problem, I'd make sure that I wasn't running a Breezy kernel with a Dapper system.

Meanwhile, a half hour of google/linux led me to this Q & A. The URL is a link to the question , but that page links to the answer which MAY work for you.

[Liam]

Re: kernel panic after adept upgrade

I have checked the original CD I did the install off in May and the readme file says this is Dapper version 6.06 31March 06.

This is not a dual boot machine.

It boots and performs fine when I select to boot on 2.6.15-19-386 but since recent adept update won't boot successfully with any of the later kernels (which it used to do OK)

Does anyone think my problem is due to this being a fairly early basic spec machine? WindowsXP used to run on this machine OK, (albeit fairly slowly) and 2.6.15-19-386 and Open Office performs satisfactorily.

Any further suggestions much appreciated.

[askrieger]

Re: kernel panic after adept upgrade

Did you follow the instructions for making initrd images for your newer kernels?

[Liam]

Re: kernel panic after adept upgrade

No I didn't I am going to try this now. Thanks for the help I am sure you have put your finger on the problem I am having.

I noted in the boot commands for later kernels, I am missing the line "initrd /boot/initrd.img-2.6.15.XX-386" which appears in the boot commands for the kernel I can boot.

I added this line in the boot commands and now I get "Error 15: Unable to find image"

So I am sure you are indicating the right track I need to go down.

[Liam]

Re: kernel panic after adept upgrade

Have now followed the link and tried to make initrd.img for 2.6.15-26-386

It seems Daper 6.06 doesn't support mkinitrd so I tried

mkinitramfs -0/boot/initrd.img-2.6.15-26-386 2.6.15-26-386

Which I suspect would have worked fine...

but on using this command I get the error message "cant find image 2.10.15-26-386.

It seems this has got waylaid somewhere? somehow?

How do I get it back. I had hoped that Adept updater could simply take care of this for me?

[Liam]

Re: kernel panic after adept upgrade

Yay problem fixed!

It seems that I had some how broken adept updater (I think I managed to crash my ADSL connection halfway through a download/update).

Using the "useful tips for Newbie forum" and the excellent steerage from Askreiger (many thanks for your help).

I managed to run "apt-get update" & apt-get upgrade (I assumed this updated and upgraded what got broken when I broke adept updater)

I was then able to run adept updater successfully

Following this I ran

"mkinitramfs -o/boot/initrd.img-2.6.15-26-386 2.6.15-26-386"

and I am now booting successfully on this kernel.

I barely understand what I have done but it is now working again and I know twice as much about Linux (which is to say EXTREMELY little) than I knew a week ago.

Many thanks for the help.