nice plugin btw. - I try to get it running behind a reverse proxy. If I test it, after two login attempts I got all entries, a mail and the iptables entry with “reject-with icmp-port-unreachable” - but I think here is the problem.
Via tcpdump I got the IP from the reverse proxy and not the real ip. I enabled the x-forwarded-for header for the apache2 and activated the reverse proxy in the plugin - but how can I do that with fail2ban?