Unblock a user from fail2ban

Posted on January 22, 2010 | Category: Comcast, Informational, Linux, Linux Distributions, Networking, Server, Ubuntu, bash, ssh

Last month my Comcast static ip address changed. Yes, I know that a static ip address is supposed to be “static.” However, each of the previous two times I was configured, the representatives gave me an ip within their non-static blocks. Fun. This transition led me to unknowingly trigger fail2ban for my SSH protocol, an intrusion prevention framework installed on my Ubuntu Server. Now that I blocked myself, how would I unblock myself? A fellow UbuntuForums contributor helped me out. Since I could not unblock myself remotely at the specific ip address, I had to wait to get home and do the operations manually.

iptables -D fail2ban-SSH -s xxx.xxx.xxx.xxx -j DROP

Also from the same post, is pannemanm’s jail.local file. I oftentimes find it helpful to post various config files like this. It can help me, or someone else, in the future.

# The DEFAULT allows a global definition of the options. They can be override
# in each jail afterwards.

[DEFAULT]

# "ignoreip" can be an IP address, a CIDR mask or a DNS host. Fail2ban will not
# ban a host which matches an address in this list. Several addresses can be
# defined using space separator.
ignoreip = Enter the IP addresses to ignore here

# "bantime" is the number of seconds that a host is banned. 172800 seconds = 48 hours
bantime = 172800

# A host is banned if it has generated "maxretry" during the last "findtime"
# seconds.
findtime = 600

# "maxretry" is the number of failures before a host get banned.
maxretry = 3

# "backend" specifies the backend used to get files modification. Available
# options are "gamin", "polling" and "auto". This option can be overridden in
# each jail too (use "gamin" for a jail and "polling" for another).
#
# gamin: requires Gamin (a file alteration monitor) to be installed. If Gamin
# is not installed, Fail2ban will use polling.
# polling: uses a polling algorithm which does not require external libraries.
# auto: will choose Gamin if available and polling otherwise.
backend = auto

# This jail corresponds to the standard configuration in Fail2ban 0.6.
# The mail-whois action send a notification e-mail with a whois request
# in the body.

[ssh-iptables]
enabled = true
filter = sshd
action = iptables[name=SSH, port=ssh, protocol=tcp]
sendmail-whois-lines[name=SSH, dest=mailaddress, sender=sender address]
logpath = /var/log/auth.log
maxretry = 3

[vsftpd-iptables]
enabled = true
filter = vsftpd
action = iptables[name=VSFTPD, port=ftp, protocol=tcp]
sendmail-whois-lines[name=VSFTPD, dest=mailaddress, sender=sender address]
logpath = /var/log/vsftpd.log
/var/log/auth.log
maxretry = 3

[apache-iptables]
enabled = true
filter = apache-noscript
action = iptables[name=APACHE, port=http, protocl=tcp]
sendmail-whois-lines[name=APACHE2, dest=mailaddress, sender=sender address]
logpath = /var/log/apache2/error.log
maxretry = 3