Knot DNS is open-source. It is completely free to download and use. The source code is available under GPL license. Our development process is transparent and driven by the needs of community and donating users.
Knot DNS provides essential DNS features including incremental zone transfers (IXFR), dynamic updates (DDNS) and response rate limiting (RRL). More advanced features include automatic DNSSEC signing, dynamic A/AAAA/PTR records synthesis, and rapid on-the-fly reconfiguration.
The server was designed to meet the needs of root and TLD name servers. It is capable of a non-stop operation. The responding code is completely lock-free and the server is therefore capable of achieving a very high response rate.
Secure and stable
The code is being constantly checked by an extensive testing suite to attain stability, assure interoperability with other DNS implementations, avoid performance regressions, and circumvent possible security-related problems.