Hi all. During my upgrade from Debian 10 to 11 and then to 12, I of course had to restart the server a few times. I couldn’t figure out why each time I restarted it seemed my server free space was reduced by 2gb. I initially thought it was that the packages didn’t clear properly. I had to drill down with
du -hxd 1 /
to see where all the space was taken. It lead me to /var/lib/fail2ban having 22gb in files. A whole bunch of dated .sqlite3 files.
I stopped fail2ban, deleted the dated files and restarted it.
I found a post about someone on a plesk server having the same issue.
Unless I’ve misunderstood the post, there was a bug in fail2ban that had been fixed. That certainly wasn’t true for me. This is the plesk discussion:
It might be useful for people to check and see how much fail2ban is stealing from their servers.