Terms of use

Last updated: 25 October 2026.

By using fail2ban.dev ("the site") you agree to these terms. If you don't agree, please don't use the site.

Informational content, provided as is#

The site publishes documentation, guides, comparisons and browser-based tools about the open-source fail2ban software. Everything is provided for general information, "as is" and "as available", without warranties of any kind, express or implied, including fitness for a particular purpose, accuracy, completeness or non-infringement.

We check pages against the fail2ban source code and official documentation (see how pages are checked), but software changes, distributions patch things differently and mistakes happen. A configuration that works on one system may behave differently on yours.

Test before production#

Firewall and ban configuration can lock you out of your own server. Before applying anything from this site to a production system:

• read and understand the configuration or command;
• test it on a non-critical system or with a console session open;
• whitelist your own addresses with ignoreip before enabling new jails;
• keep backups of the files you change.

The best practices page collects precautions we recommend.

Your responsibility for security#

fail2ban and the measures described here reduce some risks; they don't make a system secure on their own. You are solely responsible for the security, configuration, availability and legal compliance of the systems you operate, including any decision to block, report or log third-party IP addresses. Nothing on the site is professional security, legal or compliance advice.

Limitation of liability#

To the maximum extent permitted by law, fail2ban.dev and its operators are not liable for any direct, indirect, incidental, consequential or special damages — including downtime, data loss, lockouts, security incidents or lost revenue — arising from the use of, or inability to use, the site, its content or its tools. Where liability can't be excluded by law, it is limited to the minimum the law allows.

The browser tools#

The tools run locally in your browser and are provided without any guarantee that their results match fail2ban's behaviour in every case. Always confirm a filter with fail2ban-regex on your own system before relying on it. What you paste into the tools stays on your device, as described in the privacy policy.

Trademarks and independence#

"fail2ban" is the name of an open-source project and belongs to that project. fail2ban.dev is an independent site; it is not operated, endorsed or sponsored by the fail2ban project or its maintainers. Other product names mentioned on the site (for example operating systems, firewalls, cloud services and other security tools) are trademarks of their respective owners and are used only to identify those products.

Licensed material from fail2ban#

fail2ban is free software licensed under the GNU General Public License, version 2 or later (GPL-2.0-or-later). Configuration excerpts quoted on the site — filter definitions, actions, defaults from jail.conf and similar — are taken from the fail2ban source and remain under that license and the copyright of their authors. Your rights to use those excerpts come from the GPL, not from these terms.

Our content#

Apart from the GPL-licensed excerpts above, the text, explanations, page design and tools on the site are the work of fail2ban.dev. You are welcome to:

• copy configuration snippets and commands into your own systems, scripts and internal documentation;
• quote short passages with a link back to the source page.

Please don't republish whole pages or substantial parts of the site, or present them as your own, without permission.

Third-party links#

The site links to external websites, such as the fail2ban GitHub repository, distribution package pages and the documentation of other software. We don't control those sites and aren't responsible for their content, availability or practices. Commands that download software from third parties are shown for convenience; review what you download before running it.

Acceptable use#

Don't use the site or its tools to attack, overload or disrupt it or other systems, and don't attempt to access parts of the site that aren't public. Automated access must be reasonable in volume and respect robots.txt.

Changes#

We may update these terms. The "last updated" date above shows when they last changed, and continued use of the site after a change means you accept the updated terms.

Contact#

Questions about these terms: see the contact page.