With a small codebase, the PowerDNS Recursor is an advanced resolver currently serving the DNS resolving needs of over 40 million Internet connections. Besides high performance (using kqueue or epoll, over 50 thousand qps on commodity hardware), it provides advanced anti-spoofing measures. In addition, the program caches server performance and timeouts, making it both network and user friendly. It also has built-in hooks for making graphs with rrdtool, providing insight into nameserver performance.License: GNU General Public License (GPL)Changes:
This version fixes two unfortunate bugs, one with slight security implications. The first bug impacts heavily loaded servers trying to resolve domains with nameservers broken in a specific way. The other bug implies that the new random generator was not used for UDP source port selection.

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