fail2ban

Bans hosts that show malicious signs such as too many password failures.

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                   v1.1.2.dev1            20??/??/??

Fail2Ban: ban hosts that cause multiple authentication errors

Fail2Ban scans log files like /var/log/auth.log and bans IP addresses conducting too many failed login attempts. It does this by updating system firewall rules to reject new connections from those IP addresses, for a configurable amount of time. Fail2Ban comes out-of-the-box ready to read many standard log files, such as those for sshd and Apache, and is easily configured to read any log file of your choosing, for any error you wish.

Though Fail2Ban is able to reduce the rate of incorrect authentication attempts, it cannot eliminate the risk presented by weak authentication. Set up services to use only two factor, or public/private authentication mechanisms if you really want to protect services.

Since v0.10 fail2ban supports the matching of IPv6 addresses.

This README is a quick introduction to Fail2Ban. More documentation, FAQ, and HOWTOs to be found on fail2ban(1) manpage, Wiki, Developers documentation and the website: https://www.fail2ban.org

Installation:

Fail2Ban is likely already packaged for your Linux distribution and can be installed with a simple command.

If your distribution is not listed, you can install from GitHub:

Required:

  • Python >= 3.5 or PyPy3
  • python-setuptools (or python3-setuptools) for installation from source

Optional:

To install:

tar xvfj fail2ban-master.tar.bz2
cd fail2ban-master
sudo python setup.py install

Alternatively, you can clone the source from GitHub to a directory of your choice, and do the install from there. Pick the correct branch, for example, master or 0.11

git clone https://github.com/fail2ban/fail2ban.git
cd fail2ban
sudo python setup.py install

This will install Fail2Ban into the python library directory. The executable scripts are placed into /usr/bin, and configuration in /etc/fail2ban.

Fail2Ban should be correctly installed now. Just type:

fail2ban-client -h

to see if everything is alright. You should always use fail2ban-client and never call fail2ban-server directly. You can verify that you have the correct version installed with

fail2ban-client version

Please note that the system init/service script is not automatically installed. To enable fail2ban as an automatic service, simply copy the script for your distro from the files directory to /etc/init.d. Example (on a Debian-based system):

cp files/debian-initd /etc/init.d/fail2ban
update-rc.d fail2ban defaults
service fail2ban start

Configuration:

You can configure Fail2Ban using the files in /etc/fail2ban. It is possible to configure the server using commands sent to it by fail2ban-client. The available commands are described in the fail2ban-client(1) manpage. Also see fail2ban(1) and jail.conf(5) manpages for further references.

Code status:

  • CI

Contact:

Bugs, feature requests, discussions?

See CONTRIBUTING.md

You just appreciate this program:

Send kudos to the original author (Cyril Jaquier) or better to the mailing list since Fail2Ban is "community-driven" for years now.

Thanks:

See THANKS file.

License:

Fail2Ban is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Fail2Ban is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with Fail2Ban; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA