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Linux : unable to boot : Kernel panic

Hello,

After restarting my server, i receive a "Kernel panic : not syncing vfs unable to mount root fs on unknown-block"
The distro is : ubuntu-server 10.1 and i have a rescue disk where i have try in chroot to :

apt-get purge linux-image
update-grub

to fix the boot sequence like some guides founded on web but nothing change and i stay with my kerne-panic

Appreciate any  help

Thanks in advance
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SA-IT
Asked:
SA-IT
1 Solution
 
odintsovCommented:
Hello,

Could you show full kernel boot log (not only error about vfs)?
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Darr247Commented:
I believe when you do
apt-get purge linux-image
you need to specify the latest kernel or it doesn't know which one to uninstall.
You should find those in the /boot/ subdirectory.
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SA-ITAuthor Commented:
Hi Odintsov,

I found nothing on /var/log except outdated logfiles.
My kernel does'nt boot at all and the exact message is : "kernel panic 1.645097 : not syncing vfs unable to mount root fs on unknown-block"

My Linux system is installed on virtual machine but there is nothing changed on my environment.

I think system is trying to boot on a kernel who isn't install
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SA-ITAuthor Commented:
Hi Darr247,
I have specified the kernel and with the "uname -a" commande i have see that the downgrade process successfuly .
I have made a "update-grub" and "upgrade-grub2" but i'm not sure grub is used on my server.

thanks for all
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SA-ITAuthor Commented:
I have found way to display grub menu ( hold shift key ) and in rescue mode i have somes informations maybe usefull

(Look at the capture)

Thanks for all
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SA-ITAuthor Commented:
i have found that my /boot partition was full.

there is probably the reason cause the issue?
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Darr247Commented:
How many kernels are installed?

What version of grub do you have, exactly?
Run
grub-install -v
to find out.
In 1.99 and newer, it only shows you the latest kernel in its menu, and you have to choose the Previous Linux versions
entry to display a list of the older kernels (on the initial menu it should also offer a chance to run memtest86). If you have 8 or 10 older kernels, you might want to pare those down to 3 or 4 to make more free space on your /boot partition... uninstalling/purging the oldest images first. I would reboot between removing each one, so if something goes wrong, you'll know at exactly what point it messed up. It's a good idea to keep at least 2 backup kernels in case you discover incompatibilites in the newest kernel[s].
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SA-ITAuthor Commented:
Hi Darry,

There was a lot of kernel installed but i have cleaned yesterday with "apt-get remove linux-server-2.6.32-3*" to remove all version except last relase 2.6.32-45.
My grub version is 0.97

I have successfully power on my machine on very old kernel yesterday but with no eth  interface. Now
this is a list of files on /boot
 list on /boot
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SA-ITAuthor Commented:
It's really strang because when i hold shift key on boot i get a grub menu where the version is différent

grub2?
Thanks all for ur help
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Darr247Commented:
You may have 0.97 installed, but grub 1.98 (as shown in the screen cap above) is being used.

0.97 is "legacy grub"; 1.98 and later is called grub2 (1.97 was grub2 beta).

You should refer to https://help.ubuntu.com/community/Grub2
for complete instructions to understand your version of grub... you can't just edit menu.lst like with legacy grub (grub2 does not use menu.lst at all... if it's present, that's because you have 0.97 installed, too).
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gheistCommented:
purge deletes everything ignoring dependencies. Congratulations with uninstalling kernel. Sort of there is a copy con kernel on install CD/DVD which you can install using upgrade procedure.

Effect will be similar removing upstart/initscripts and/or libc or lvm2.... Just some packages are needed to boot the system..
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SA-ITAuthor Commented:
I have simply reinstall my server from scratch.
Thanks all for all proposition.
Best regards
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Darr247Commented:
In http:#a38721717 I said:
I would reboot between removing each one, so if something
goes wrong, you'll know at exactly what point it messed up.
It's a good idea to keep at least 2 backup kernels in case you
discover incompatibilites in the newest kernel[s].

Do keep that in mind in the future when removing old kernels.
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SA-ITAuthor Commented:
thanks for advices
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