This partition is filling up on my server: /dev/sda2

I assume that it's some type of log files? How do I delete them to free up some space?

I'd be careful... might really want to consider contacting your server provider (if mananged) or paying someone a little bit of money to take care if it.... you REALLY don't want to start deleting things you aren't familiar with :)

If those are logs, the rotate them first so f.e. WebAlyzer or Analog get their share and THEN delete them. BUT BE CARFUL!

A command I used on a Cobalt RaQ 4i was this "split_logs web </home/log/httpd/access" in order to do exactly that. Consult someone or something to find the right command for log-rotation.