Search for errors
grep fail2ban /var/log/syslog
Starting authentication failure monitor: fail2banERROR Found no accessible config files for ‚filter.d/sasl‘ under /etc/fail2ban
ERROR Unable to read the filter
ERROR Errors in jail ’sasl‘. Skipping…
Create file by staring at it
vim /etc/fail2ban/filter.d/sasl.conf
Dies einfügen :
nothing fancy
# Fail2Ban configuration file
#
# Author: Yaroslav Halchenko
#
# $Revision: 728 $
#
[Definition]
# Option: failregex
# Notes.: regex to match the password failures messages in the logfile. The
# host must be matched by a group named "host". The tag "" can
# be used for standard IP/hostname matching and is only an alias for
# (?:::f{4,6}:)?(?P[\w\-.^_]+)
# Values: TEXT
#
failregex = (?i): warning: [-._\w]+\[\]: SASL (?:LOGIN|PLAIN|(?:CRAM|DIGEST)-MD5) authentication failed(: [A-Za-z0-9+/]*={0,2})?$
# Option: ignoreregex
# Notes.: regex to ignore. If this regex matches, the line is ignored.
# Values: TEXT
#
ignoreregex =
Restart service
/etc/init.d/fail2ban restart
