Booting the Server After Upgrade

You may remember last time that I was unable to boot after upgrade to Ubuntu 7.04. The error was:

Check root=bootarg cat /proc/cmdline
or missing modules, devices: cat /proc/modules ls /dev
ALERT! /dev/disk/by-uuid/7e6ada37-87a7-475b-9a12-53129119ea05 does not exist. Dropping to a shell!

I looked around quite a bit to find a solution. Some suggested that the uuid in /boot/grub/menu.lst didn't match the uuid of the drive. Unfortunately, from the initfs prompt, I couldn't get to the /dev/disk/by-uuid directory.

What I could do was mount the drive:

modprobe ide-disk
modprobe ide-generic
mount -t ext3 /dev/hda1 /root

and edit the grub menu:

chroot /root nano /boot/grub/menu.lst

I tried changing that file to point to a drive rather than a uuid (I can't find page anymore, so no example), but that didn't help. It only removed the uuid from the error message.

Finally, after over two weeks of this, I broke down and reconnected the CD-ROM to the server to boot from the install CD in rescue mode. Regular readers will remember that I don't have an optical drive on this machine, since I didn't think I would need it after installation, and that it requires a low profile drive that is a little pricey. (I may get a DVD burner someday for backups, although today I can't find one to link to.) So, I have to crack open the case and hang a full sized drive off the side of the chassis like this.

I was able to boot to the rescue disk and mount the main drive partition. A quick look in /dev/disk/by-uuid showed that the uuid on the drive did match the one entered in menu.lst and in fstab. So, after all of that work, I was still nowhere.

One more thing to try, this page suggested that I build a new initrd image file with this command:

dpkg-reconfigure linux-image-2.6.20-15-386 (substitute the name of your kernal as found in menu.lst)

And, wouldn't you know it, it worked! I can now boot to the server, and connect via ssh.

Still, there is now a new problem; I can't connect to the Samba share. All of the files are still there and the Samba configuration file haven't changed, but we're getting permission errors. The solution for this will be the subject of a later (hopefully not much later) post.

One more thing, the steps to connect the temporary CD drive reminded me that the BIOS settings still are not saved if the power cable is removed - even after I changed the battery. This is a problem only because the POST hangs on two errors: no keyboard connected and no floppy drive found. I don't know what to do about this, but every time the power goes off (around every three months), I have to reconnect a keyboard and monitor to get the server going again. I may have to take it to the local shop.