Friday, January 30, 2015

Dual booting Centos: /boot/boot/grub.conf kernel root=/dev/sda0 VS root=UUID=X-X-X-X-X VS root=/dev/mapper/luks-X-X-X-X-X

I'm adding this to my blog because I'm not sure where else to post technote ...

From: kernel-2.6.32-504.3.1 To kernel-2.6.32-504.3.3

The nearest I report I found to my problem was:
[SOLVED] LVM on Luks cannot find device

I dual boot linux/Centos.  x86_64 on one partition, and i686
Basically back in Dec 2014 I upgraded my kernel on one of my partition

However "something" then cleaned up all my  "x86_64" kernels and modules...
It was manifested with the message "cannot load module.dep"

FATAL: Could not load /lib/modules/ No such file or directory.

The fix is to reinstall the missing kernel... IF you can boot.

This is made a little tricky when one partition is strictly i686 and the other is x86_64... I ended up booting into single user, doing a rpm install --ignorearch on i686, then manually mounting the x86_64 copying all the x86_64 kernel files (rpm -ql kernel)  from the i686 partition...

Interestingly this whole process is a bit of a time bomb, because the problem only manifested itself 6 weeks after previous kernel upgrade.  So I am not sure what "update" cleaning out all the previous kernel and modules...

Alternatively you may be abel to an easier solution by running the "recovery shell" or booting from a recovery disk/USBDrive.


ps.  If you know what is "cleaning up" the old kernels (esp. kernels on that partitions RPM database, then let me know)  Cheers.