beware is a small DNS server that can have nameserver responsibility delegated to it and that can return a set of authoritative "IN A" records to a client. Given a list of hosts for a certain domain name, it also tests for services specified and will only return IP addresses for currently reachable services.
Asynchronous DNS Resolver for Haskell is a library that provides an asynchronous DNS resolver on top of GNU ADNS. Not all options are supported, but A, MX, and PTR lookups work nicely. There is also support for retrieving generic RR types, CNAMEs, and for NSEC zone walking. The library can be expected to work with fine ADNS 1.4 or later. It might also work with version ADNS 1.3, but that hasn’t been tested.
CD Linux Server is an embedded Linux system on a bootable live CD. It can be used to set up mail, Web, file, FTP, proxy, DHCP, DNS, MySQL, LDAP, and other services very quickly. The mail server includes antivirus, antispam, and mail recorder features. It can be used for free for up to 10 accounts, while the advanced version is licensed for an unlimited number of users. There is not any restriction against the time.
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.
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.
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.