fail2ban monitor and ban really persistent attackers

fail2ban.conf

# /etc/fail2ban/filter.d/fail2ban.conf

# Fail2Ban configuration file
#
# Author: Tom Hendrikx
#
# $Revision$
#

[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 "<HOST>" can
#          be used for standard IP/hostname matching and is only an alias for
#          (?:::f{4,6}:)?(?P<host>\S+)
# Values:  TEXT
#

# Count all bans in the logfile
failregex = fail2ban.actions: WARNING \[(.*)\] Ban <HOST>

# Option:  ignoreregex
# Notes.:  regex to ignore. If this regex matches, the line is ignored.
# Values:  TEXT
#

# Ignore our own bans, to keep our counts exact.
# In your config, name your jail 'fail2ban', or change this line!
ignoreregex = fail2ban.actions: WARNING \[fail2ban\] Ban <HOST>

jail.conf

# add to  /etc/fail2ban/jail.conf

[fail2ban]
enabled = true
filter = fail2ban
action = iptables-allports[name=fail2ban]
        sendmail-whois[name=fail2ban]
logpath = /var/log/fail2ban.log
# findtime: 1 week
findtime = 604800
# bantime: 1 week
bantime = 604800

For the benefit of any one who is having a problem with this jail. You may want to try the solution that worked for me. Hope it works for you. You will have to change both the failregex and the ignoreregex to the ones below.

failregex = fail2ban.actions\[(.*)\]: WARNING \[(.*)\] Ban <HOST>

ignoreregex = fail2ban.actions\[(.*)\]: WARNING \[fail2ban-reban\] Ban <HOST>