Grub or /boot boot problem [Solved]

[kwacorn]

I used Rigo to do the sabayon-weekly updates (16th September 2012), afterwards Rigo displayed a message about packages that were no longer needed, those packages being kernels 3.0 and 3.1, I also have kernels 3.2 to 3.5 installed. I clicked on the links in the message and selected to uninstall them - although Rigo said it was busy there was no CPU or disk activity even though I waited a long time to see if anything would happen.

After quitting Rigo and rebooting the system the GRUB menu now displayed only two options:

Sabayon GNU/Linux
Advanced options for Sabayon GNU/Linux

Selecting the Advanced option displays the menu of kernels, which is the normal menu I would usually see. Selecting any option from the GRUB boot menu first results in the message:

error: file not found

repeated three times followed by various normal bootup messages until the last message stating:

!! Could not find the root block device in .

and the prompt:

root block device() ::

I tried /dev/sda4, which I would expect it to be, but without success. /boot is on its own separate partition but the rest of the system is on logical volumes on an encrypted partition, sda4, so I would normally expect to see a request for the passphrase at this point. If I boot from a live installation media I can manually enable the encrypted partition and mount the logical volumes and see the files on them.

I am not sure how to proceed to identify and fix the problem so the system can be fully booted, could someone advise please?

[flebber]

If you can boot using a live cd/usb and mount the sabayon partitions /dev/sda4 according to what you posted. If you run update-grub2 then it may fix the incorrect entries you have in grub.

[kwacorn]

There does not appear to be an update-grub2 on my Sabayon systems. However your post and http://forum.sabayon.org/viewtopic.php?f=86&t=27927 suggest this is a grub problem (I was unsure due to how it came about), that post suggest running:

Code: Select all

grub2-install /dev/sdX   #replace sdX by the partition where your grub is located
grub-mkconfig -o /boot/grub/grub.cfg

However running those results in the error message

Code: Select all

Failed to load ZFS module stack
Load the module manually by running 'insmod <location>/zfs.ko' as root.

May be that is because I have booted from Live Sabayon 7 media and chroot to the installed Sabayon 10 system?

[stubborn_d0nkey]

The root block device problem sounds like an error/omission with your grub entry. From your post I get the sda4 is an extended partition, so that can't be your root block device (think of sda4 as merely a container, not a partition itself), the root block device would be the logical (sdaX where X is 5 or more) partition that is your root partition, you can try entering that when it prompts you for the root block device. I, think, though I'm not sure, that adding real_root=/dev/sdaX to your grub entry (in the linux/kernek line) will make it unnecessary to manually do it each time.

Also, do you get that ZFS message when running grub2-install or grub-mkconfig or both?

P.S. This may be silly, but im guessing you tried he first entry (the one not in the advanced menu)

[kwacorn]

Thanks for your replies and help.
I did not solve this problem directly, instead I used it as an opportunity to do a fresh install, using Sabayon 10, and fixed a couple of other minor issues in the process. It was a smooth install and I seem to have a more tidy and clean system than my previous and first Sabayon install of v.7, so I am happy with this as a solution.