I removed the ignoreip setting from the nagios section. As pointed out, it is redundant here. Nagios server, under normal circumstances should not trigger any access errors, and would be included in the global ignoreips anyway.
The second failregex was supposed to catch an error concerning an ACL denial over IPv6, but this message is no more generated by the nrpe version (v2.15) that introduced the IPv6 support, so the first failregex seems to be sufficient.
The dot at the ignoregex did not belong there. Somehow it was added during the copying and pasting. Thanks for reporting it, I did not see it. Otherwise, empty ignoregexes are in all filters, and if they are missing, fail2ban client shows warnings when starting the filter, which I prefer avoiding.
I am sorry, I installed the Win GIT, but still did not learn how to work with it, so am posting here again. This time, I'll avoid posting two pull requests, so please fix the dovecot.filter for me, if you don't mind.
This current filter does not match authentication errors in my Dovecot logs (two different lines attached). First of all the session string is at the end (after the optional TLS string), and not before it as it is now in the filter. I don't see it anywhere in the other logs here in the opposite order, hence I assume it is the rule for all installations. And then, the session ID can include also other characters than those matched by \w+ (i.e. the slash and the plus signs in my case), hence it needs to be \S+ instead. Personally, I'd do the regex much less restrictive than it is, but if I follow the current logics, the following form works:
<pre>^%(__prefix_line)s(pop3|imap)-login: (Info: )?(Aborted login|Disconnected)(: Inactivity)? \(((no auth attempts|auth failed, \d+ attempts)( in \d+ secs)?|tried to use disabled \S+ auth)\):( user=<\S*>,)?( method=\S+,)? rip=<HO
ST>, lip=(\d{1,3}\.){3}\d{1,3}(, TLS( handshaking)?(: Disconnected)?)?(, session=<\S+>)?\s*$</pre>
As explained in https://github.com/grooverdan/fail2ban/pull/4, in Exim there can be used plenty of other standard authentication names, and in fact the names can be custom. The failregex in Exim filter should catch authentication errors regardless of the name of the authentication. Hence replacing the plain|login with the general \w+