FDNS is an encrypted DNS proxy designed for small networks and Linux desktops. Lean and mean, it protects your computer from some of the most common cyber threats, while also improving privacy and the system performance.

FDNS is written in C and licensed under GPLv3. We use only DoH , DoT, and DoQ services from non-logging and non-censoring providers, while preferring small operators such as open-source enthusiasts and privacy-oriented non-profit organizations.

Features

• Network of 200+ non-logging/non-censoring service providers spread across the globe. Access to specialized services such as family filtering, adblocking, and security.
• Blocking ads, trackers, coinminers, phishing.
• DNS resolver cache and DNS firewall targeting various DNS attack techniques.
• Highly scalable multi-process design and built-in support for various security technologies such as seccomp, Linux namespaces, and AppArmor.
• Seamless integration with Firejail Security Sandbox.

About us

FDNS is a community project. We are not affiliated with any company, and we don’t have any commercial goals. Our focus is the Linux desktop. Home users and Linux beginners are our target market. The software is built by a large international team of volunteers on GitHub. Expert or regular Linux user, you are welcome to join us!

Security bugs are taken seriously, please email them to netblue30 at protonmail.com.

• Webpage: https://firejaildns.wordpress.com
• Development: https://github.com/netblue30/fdns
• Download: https://github.com/netblue30/fdns/releases
• Documentation: https://github.com/netblue30/fdns/wiki
• Support: https://github.com/netblue30/fdns/issues (GitHub)
• FAQ: https://github.com/netblue30/fdns/wiki/FAQ

News

November 2025 – released FDNS 0.9.76. This release brings in support for DNS over QUIC, a much larger server list, a full rebuild of the adblocking filters, and lots of bugfixes. Release Notes

October 2024 – bugfixes! Release Notes

September 2024 – released FDNS 0.9.74. The software went trough a major cleanup, and several rarely used features have been removed: –debug-ssl, –proxy-addr-any, –cache-ttl, –log-timeout, –blacklist, –qps, –unlist, –disable-local-doh, –disable-syslog, –transport, and –fallback-only. In addition, we implemented several new features, such as keepalive autodetection, streamlined some of the existing functionality, a full rebuild of adblock filters, and lots of bugfixes. The server count is around 280. Release Notes

October 2023 – released FDNS 0.9.72. In this release we continue the development of our nxdomain tool, streamlined some of the least-used features, and added --disable-syslog command line option. The adblock filters have been fully rebuilt, we introduced a new phishing filter, and updated the server list. Release Notes

March 2022 – released FDNS 0.9.68: small number of new features, server and adblocker list updates, bugfixes. Release Notes

May 2021 – released FDNS 0.9.66. This release brings in support for a servers.local file in etc directory, added several new commands for server file, new command line options, a new utility program (nxdomain) to clean up expired adblocker domains, removed non-profit tag from the server list, and lots of bug fixes. The adblocker filter and the server list have been updated. FDNS packages are currently available in Arch Linux (AUR) and Slackware (Slackbuilds). Release Notes

January 2021 – released FDNS 0.9.64.2: –blocklist, –blocklist-file and –fallback-server command line options, UDP port number randomization, collapse eastamerica and westamerica in americas zone, several new build options,Intel 32 bit architecture support, server list update and bug fixes. Release Notes

October 2020 – released FDNS 0.9.64, featuring a number of new command line options, monitor enhancements, server list updates and bug fixes. Starting with this release, AppArmor is supported in Arch Linux. Release Notes

September 2020 – released FDNS 0.9.62.10. In this release we are adding support for DNS over TLS and HTTP 1.1, restructure geographical zones, keepalive timer randomization, server list updates and bugfixes. Release Notes

June 2020 – released FDNS 0.9.62.8. In this release we are replacing HTTP 1.1 with HTTP 2 in the protocol stack, and we are adding a lot of new DoH servers to our list – only https://commons.host brings in a network of more than 20 geolocated DoH servers! We also added several new command line options, and fixed quite a number of bugs. Arch Linux just started packaging and distributing fdns in AUR. Release Notes

May 2020 – released FDNS 0.9.62.6. In this release we are adding whitelisting domains functionality, resizable monitor window, support for multiple FDNS proxies running on the same system, enforcing NXDOMAIN for blacklisted domains, a server list update and bugfixes. A lot of development went into our regression testing, we started tracking gcov-based code coverage for our tests (published on https://netblue30.github.io/regtest/), and integrated lgtm.com security scanner in our ongoing development process. Release Notes

March 2020 – released FDNS 0.9.62.4. In this release we introduce CNAME cloaking protection, DNS rebinding protection, SNI cloaking whenever possible, we disable all known DoH service on the local network, and we increased DNS cache TTL to 40 minutes. Also bugfixes and a DoH server list update.

February 2020 – released FDNS 0.9.62.2. The project is feature-complete! We added over 60 new DNS over HTTPS servers, documentation, an automated test framework, and lots of bugfixes.

December 2019 – released FDNS 0.9.62. This is the first release of the project. (Download, Documentation, FAQ)