Posts tagged karmic

Reinstalling A Corrupted Ubuntu Karmic Upgrade

I have previously posted about my own Karmic upgrade problems. In my case, the system crashed in the middle of the upgrade (due to my own fault, nothing to do with the upgrade itself as far as I know), causing my half-upgraded system to be unable to mount the root filesystem and dropping me into a maintenance shell.

I’ve always tried to promote Linux use among friends and family which means I also provide support as required. Yesterday, a friend of mine brought me her laptop with a similar problem to the one I had: in her case, she thinks that she lost her internet connection in the middle of the Jaunty to Karmic upgrade. In any case, her half-upgraded system would neither boot nor allow a root prompt. The error message on the console was:

mountall: symbol lookup error: mountall: undefined symbol: udev_monitor_filter_add_match_subsystem_devtype
init: mountall main process (310) terminated with status 127

I tried a couple of things: first, I used an old Jaunty disk to boot the machine, mounted the old root filesystem and attempted to use chroot so that I could complete the upgrade.

mkdir /media/disk
mount /dev/sda5 /media/disk
chroot /media/disk

Unfortunately, this didn’t work because I had no network devices available in the chroot jail, and I couldn’t find any obvious way to sort that out. Similarly, I downloaded a new iso of Ubuntu Karmic hoping to use it as the apt source for the upgrade, but I couldn’t access the cd drive either, even using apt-cdrom to set it up. As before, a bit more effort might have sorted this out, but I decided to solve the problem by doing a complete re-install of Karmic over top of the previous one.

I backed up the /etc and /home directories to an external hard drive first to be safe. To my delight, the reinstall worked fine and didn’t clobber any of the existing user data on the drive. During the partioning step, I selected the manual option. I changed /dev/sda5 (which in this case was the old Ubuntu root filesystem) to mount as “/” but didn’t check the box for it to be formatted. In the “import settings” step, I also told the installer to import user settings from the old Ubuntu install. When I rebooted, everything was up to date, and the user settings and documents were all in place as expected. Good to know!

As a final note, I should add that when I set up this system for my friend, I configured Dropbox and told her how to use it. That meant that I could’ve easily restored everything even if I’d had to do a complete format and reinstall. On my own machine, I’ve placed a symbolic link to /etc in my Dropbox folder (it doesn’t take up much space) along with linked versions of all of my important dot files — that means that, with a little effort, I can reimage and restore at any time. I will set up all my friends the same way from now on.

Logging out with the Cairo dock

I’ve decided to take advantage of my new powerful laptop and enable a little eye candy. I’ve tweaked Compiz to my liking and enabled the Cairo dock (I used the Avant Window Navigator for a couple of days and liked it as well, but Cairo is even better). I’ve been able to set up my Cairo dock to give me everything I appreciated in the old gnome panels with one exception: the user switcher applet. Cairo gives you a shut-down menu, but no way to log out of your session or switch to another user.

I have discovered the command “gdmXnestchooser” which at least lets me switch to the face browser and log in as another user, but I’d like to be able to log out of my current session sometimes in order to refresh things. I have also enabled restarting the X server (similar results to logging out) as described here. Essentially, you must go to the preferences/keyboard/layout and enable the ctrl-alt-backspace key combination. Another tool, “gdmXnestchooser” allows you to create a nested X session, but you need to install gdm-2.20 to make it work and I don’t want to risk buggering up my current setup.

One thing I love about the combination of Compiz and Cairo is the ability to dump all of my widgets (weather, clock, conky, system tray etc.) onto the compiz widget layer. I have it configured to pop up when I move the mouse to the top edge of the screen so I can instantly see the status of everything without having to use precious screen real estate or flip back to the desktop. I have the dock on auto-hide, so I can use the full screen without sacrificing usability. It is an elegant solution to the problem of trying to use a single display for many simultaneous purposes.

UPDATE: Turns out it’s easy to log out from the Cairo dock…see comment below.

Ubuntu Karmic Koala Upgrade

I have upgraded from Jaunty to Karmic on my Dell XPS 1610 and everything seems to work great.

My upgrade was interrupted (my own fault for running another application at the same time and having it crash) and caused some serious problems for a few hours while I tried to fix it. The symptom was that the system wouldn’t boot and told me that it couldn’t read from the root filesystem. In the end I solved the problem by dropping to a shell, re-mounting the root disk so I could write to it (“mount -o remount,rw /”), then running apt-get and sorting out dependency problems with python2.6 and mono-common (I finally had to delete /var/lib/binfmts/python2.5 in order for python to install properly). This process took hours and finally I was able to perform a full “apt-get dist-upgrade” from the shell, then reboot. I still had a disk error which prevented booting, but I discovered a great tip someplace to force a disk check on the root filesystem on reboot with “tune2fs -C 30 /dev/sda5″ (or whatever device).

The experience reminded me that Linux is great for people like me, but maybe not so great for others. It isn’t that Windows doesn’t have similar problems (like I said, it was my fault for crashing the system in the middle of a major upgrade), but when it does, a less-savvy user can take the machine to the corner computer shop to get it fixed.

In spite of that, Karmic has lots of great features that make it perfect for any user. I’m still noticing small changes, but so far, so good. I like the new face browser login window and I’m thrilled with the new audio control panel, which is simpler and clearer than before with new features — for example, you can now see which active applications are using the sound server and turn them on and off with a single click.