JDNSS

JDNSS is a fantastic tool for those who are searching for a reliable DNS server that is free of cost and open source. This software is written completely in Java so it provides better portability, and security compared to other DNS servers. It is currently designed to be used as a "leaf" server meaning it doesn't provide iterative or recursive lookups for clients or any form of caching. The server reads zone files provided on the command line, making it incredibly easy to operate.

Overall, JDNSS is a great tool that provides an effective solution for those needing a secure and portable DNS server. Its simplistic design makes it easy to use, and its ability to read zone files offers excellent flexibility. Those who prioritize portability and security can be rest assured that JDNSS is a high-quality solution that is perfect for their needs. So, if you're looking for an open source DNS server that is fast and secure, JDNSS might be exactly what you need.