I've upgraded all four of my machines (two home machines and two work machines) from Feisty Fawn to Gutsy Gibbon. Two were pretty simple, the other two were tricky. One still doesn't have sound, which is really frustrating. I'm going to write up the gory details for my own benefit. It'll probably be boring for you. Sorry, blogs are like that ;-)
My laptop was the easiest. I don't keep anything on its hard drive. It's pretty much used as a thin client, so I could just about do a fresh install every time. I don't like to have to reconfigure stuff from scratch though, so I did the update-manager upgrade. It was quick, under two hours, and everything seems to be working fine. Oh, except my anti-aliased fonts on emacs. Those went away for some reason. That happened on all the machines. I probably just need to add back in the right repository for that.
The kids' machine at home had a small hiccup. It's an older celery-on machine and I'm running the Xubuntu desktop. It also has two 80 GB hard drives that I have in a RAID 0 configuration, for speed (oh yeah!). The upgrade had no problems with the RAID setup, but partway through update-manager configuring all the new packages, the screensaver came on and locked the screen, and for some reason it would not take my password. I had to ctrl-alt-1, log in, and kill xscreensaver. That killed X too though, and I had to manually use dpkg --configure -a to finish the upgrade. Everything seems fine now though.
My desktop at work was a chore. It probably has a fairly non-standard setup for Ubuntu: nfs mounted home directory, nis authentication, and a whole bunch of automounted nfs directories, and dual displays. I kept getting an error about packages not being authenticated for some reason. I thought it had something to do with our proxy, or maybe the repositories were overloaded whenever I tried and I just couldn't get things downloaded properly. I tried using the alternative install CD to do the upgrade instead of the regular update-manager process, but I either had the same authentication errors, or a strange message about not being able to calculate the upgrade. I tried putting our web proxy in /etc/apt/apt/conf.d, I tried setting the proxy under System-> Preferences-> NetworkProxy, but what finally worked was setting the http_proxy environment variable in a terminal and then running update-manager from that terminal. It was weird.
I left it downloading packages and went home for the night. When I came back the next morning the screens were black and the keyboard lights were flashing. I finally use magic keys to reboot it. X wouldn't come up, so I ctrl-alt-1ed and logged in (as a local user, nis wasn't working either). I did the same dpkg --configure -a that I had to do in the kiddos laptop and that ran for a while. At some point X started and the keyboard lights flashed again. Another reboot, more dpkg, and I got to a point where I encountered the device-mapper bug. I rebooted with magic keys again, but I booted an older kernel, removed evms as prescribed, and rebooted (nicely this time) again. I was finally able to get all the way through configuring all the packages, but it said it couldn't configure partially installed packages: acpid, ubuntu-desktop, powermanagement-interface, and acpi-support. I did an aptitude remove of all of those, and then an aptitude install to get them back, and finally everything seemed to be working. I did another aptitude update and aptitude full-upgrade just to make sure, rebooted, and now everything seems to be working (except my emacs fonts, dang it!). Phew!
Home desktop system. Everything seemed to go smoothly during the upgrade, however my sound didn't work when it was all said and done. There was some other weirdness due to an odd repository that I had added, but that was easy to fix. The sound problem however has not been easy. It appears to be a known problem. See this and this and this. Yes, lspci shows that I have this audio hardware:
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02)
I tried the module-assistant steps and my audio still doesn't work. Grrr. Ubuntu, you've been so good to me for so long. Why now? Why something so basic as sound?