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.
dnscrypt-proxy acts as a DNS proxy between a regular client, like a DNS cache or an operating system stub resolver, and a DNSCrypt-aware resolver, like OpenDNS. The DNSCrypt protocol focuses on securing communications between a client and its first-level resolver. While not providing end-to-end security, it protects the local network (which is often the weakest link in the chain) against man-in-the-middle attacks. It also provides some confidentiality to DNS queries.
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.
Collax Business Server is an all-in-one Linux server for small- and medium-sized businesses. It delivers all the important network services within a heterogeneous business environment for communication, infrastructure, compliance, groupware, and storage, all in a reliable and secure way which is easy to manage. It also provides essential security functions such as firewalling and virus and spam filtering, to protect against hacker attacks, viruses, and unsolicited email messages.
ext-Dns is a core library, an extensible forward DNS server, and some additional tools designed to create DNS server solutions which are able to do any additional operation at the resolution level (running commands, rewritting replies, gathering stats, and so on), without any limit. It provides a ready-to-use solution in case you want to build a DNS server which takes additional actions at the resolution level in an easy way. That is, its design is focused on allowing people to implement whatever they like when a request is received, freeing them from most of the details which involves handling DNS protocol.
cqueues is a comprehensive event and networking library for Lua 5.2 and LuaJIT using modern Unix O(1) polling facilities. It includes libraries for buffered socket I/O, SSL/TLS sockets, DNS querying, signal handling, threading, file change notification, and X.509 key management. It natively supports Linux, *BSD, OS X, and Solaris systems without third-party dependencies, and is interoperable with any event loop that accepts plain descriptors, or is usable standalone.
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.
Unnamed un-names unwanted DNS entries. It was written to solve the problem of upstream DNS servers inserting bogus records for NXDOMAINs. It can be used to filter unwanted domain names like ads, porn, time wasters, etc. It is modular, so extensions are easy. Extensions can be written in Lua or compiled as shared objects.