With a small codebase, the PowerDNS Recursor is an advanced recursor currently serving the DNS resolving needs of over 2 million Internet connections. Besides high performance (using kqueue or epoll, over 15 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:
Modest performance improvements of around 20% were made. A number of smaller and larger issues were fixed. Importantly, compatibility with recent gcc versions was restored. The new IPv6 root-servers are now picked up automatically. Finally, domains can now be forwarded to multiple IP addresses and ports.

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