Anyone using Ubuntu Feisty Fawn should not install the kernel update to 2.6.20-16! It comes as a security update, but it includes some nasty trickery with the ATA/SATA drivers. After I installed it I could not boot anymore, because for some reason the drive names had changed!
All the SATA drives that had
/dev/sdXX names before were now called
/dev/hdXX. Even though my
/etc/fstab only contains "by-uuid" entries, all but the PATA boot drive could not be accessed.
I already suspected a hardware defect, because booting without the splash screen showed "lost interrupt" errors. I only got skeptical when I read it was on drive
/dev/sdg which I just plain do not have!
Unplugging both SATA drives at least let me boot into the system again. From what I read in Launchpad Bug #116996 booting with the previous version 2.6.20-15 should work in the meantime.
I have to admit I am pretty pissed off by Ubuntu at the moment. I really love the work they do, however sometimes they seem to be a little too fast with updates (remember the troublesome X11 update some months ago) that are critical to the system. Maybe I would not be so angry about e. g. the sound card not working properly, but come on people, changing hard disk drivers silently as part of an unrelated security update?!
The bug is several days old already and Debian already has it fixed. However for some reason there does not seem to be much movement from Ubuntu...