Dual DHCP DNS Server is a DHCP server combined with a caching DNS server that is sensitive to the names that were allocated by the DHCP server. It has built in dynamic updates, and also supports BOOTP PXE network booting and client specific options. It is self-configuring, doesn't require the creation of zone files, and uses little memory and CPU time. Either one of the two services can be turned off.
With a small codebase, the PowerDNS Recursor is an advanced resolver currently serving the DNS resolving needs of over 80 million Internet connections. Besides high performance (using kqueue or epoll, over 100 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.
PHREL is a per host rate limiter. It will track the rate of incoming traffic on a server and insert a chain into iptables when a configured threshold is crossed. The inserted chain may either rate limit or block the offending host for a period of time. The inserted chain is automatically removed when the offending host's traffic levels return to normal. PHREL is particularly well suited to protecting nameservers (DNS) from random hosts that flood requests, and to preventing SSH brute force login attempts.
YaCy is a search engine that anyone can use to index the Internet (WWW and FTP) or to create a search portal for others (Internet or intranet). The scale of YaCy is limited only by the number of users. and can index billions of web pages. In P2P mode it is fully decentralized. All users of the search engine network are equal and it is not possible for anyone to censor the content of the distributed index.
OpenNetAdmin provides a database managed inventory of your IP network (IPAM). Each host can be tracked via a centralized AJAX-enabled Web interface that can help reduce tracking errors. It also has the ability to generate DHCP and DNS configuration for individual servers from the data stored in the database. There is a command line interface for batch scripting that can be accessed remotely or locally.
PowerDNS Authoritative Server is a high-performance authoritative nameserver with a host of backends. Besides plain BIND configuration files, PDNS reads information from MySQL, Oracle, PostgreSQL, SQLite, MongoDB, and many other databases. Backends can easily be written in any language, and a sample Perl backend is provided. PDNS powers around 30-40% of all domain names in many parts of the world, including >90% of all DNSSEC domains in Europe.
adsuck is a small DNS server that spoofs blacklisted addresses and forwards all other queries. The idea is to be able to prevent connections to undesirable sites such as ad servers, crawlers, etc. It can be used locally, for the road warrior, or on the network perimeter in order to protect local machines from malicious sites.