I accidentally left two problematic repositories in my /etc/apt/sources.list - to be specific, the squeeze-updates repository (changed from "volatile"), and the sid repository. I was testing some things a while ago and needed those repos for some packages not available in the current one. However, I forgot about it and upgraded (apt-get dist-upgrade) with those repositories, and haven't experienced problems until now, prompting me to downgrade.
First, I removed the conflicting sources. Then I followed online instructions to apt pin the stable repositories to force a downgrade. After it completed, hundreds of obsolete packages remained. Being audacious, I crafted (and ran) the following command to attempt to remove them:
while :; do aptitude -y --without-recommends -f remove ?obsolete; if [ ! "$?" = "0" ];then break; fi; done
It did remove the obsolete packages, especially upstream things like the Linux 3.x kernel. However, I saw some other things that got removed, like the software that I installed before the repo change. I should have stopped everything then, but I thought I'd keep going and let it run, knowing that I can recover later. Coming back to the session window later, it had a dialog prompting me whether I want to keep or remove... my currently running kernel.
I really don't want to do a CD reinstall - I have no place to store the 20+ GBs of data (this is a VPS, and I have a very slow internet connection), and reconfiguring everything will take a LOT of time, and I need the server to be running again ASAP.
Supposedly (this is from the Debian mailing list archive), Debian users prefer to do reinstalls via APT, since this is theoretically possible. I have my own reasons to do it via APT.
Is there, at all, in any way possible, to install Debian without resorting to a CD, via APT or other means? I still have access to the Internet on my server.
I'm aiming to do reinstall the base system AND any categories that I've selected during the original installation (CLI) of Debian Squeeze.