[CentOS] New motherboard - kernel panic

Mon Apr 15 19:25:44 UTC 2013
Bowie Bailey <Bowie_Bailey at BUC.com>

On 4/15/2013 3:10 PM, Les Mikesell wrote:
> On Mon, Apr 15, 2013 at 1:54 PM, Bowie Bailey <Bowie_Bailey at buc.com> wrote:
>>> CentOS 4 - seriously???
>> Yea, it's an old system.
> If you have somewhere to copy the data,  the best approach would be to
> back it up from the rescue-mode boot, reinstall centos 6 and copy back
> anything you need - and be good for another many years.

This system is running BackupPC.  The number of hardlinks in the data 
makes copying impractical.  I may rebuild it with CentOS 6 later and let 
the backups rebuild themselves, but I don't want to do it now if I can 
avoid it.

>> There is a /etc/modprobe.conf file on the original system.  Among other
>> things, it says:
>> alias scsi_hostadapter sata_nv
>> I assume that refers to the driver for the nvidia chipset.
>> I found a modprobe.conf file in the rescue environment living in
>> /tmp/modprobe.conf.  This one says:
>> alias scsi_hostadapter ahci
>> I guess that's a driver that works with the new hardware?  I do not have
>> the ports in ahci mode in the bios.
> lsmod from the running rescue system should show the loaded modules.
> Your initrd has to include anything needed to access the hard drive
> and filesystem before you can find the others.
>> What do I need to do to make sure the driver gets into initrd?  Or do I
>> just need to make the change to /etc/modprobe.conf on the hard drive?
> I think you would change the /etc/modprobe.conf on the hard drive and
> chroot there (/mnt/sysimage) before running mkinitrd.

I figured that one out just before I received your response.  That fixed 
the bootup problem.  The changes to modprobe.conf were what was missing 
from the instructions I found online on Friday.

For future reference, this is what I did:

1) Boot into rescue mode.
2) Look at /tmp/modprobe.conf in the rescue environment to see what 
driver was in use.
3) Edit /mnt/sysimage/etc/modprobe.conf and add the driver there
4) chroot /mnt/sysimage
5) cd /boot
6) mv initrd-(kernel version).img initrd-(kernel version).img.bkup
7) mkinitrd initrd-(kernel version).img (kernel version)
8) reboot

Now I've just got to work on getting the network card going, but that (I 
hope!) should be much easier now that the system is booting.