Pdnsd

Caching (permanently, writes to disk on exit) DNS proxy-server

pdnsd is a proxy dns server with permanent caching the cache contents are written to hard disk on exit that is designed to cope with unreachable or down dns servers for example in dial-in networking. pdnsd can be used with applications that do dns lookups, eg on startup, and can’t be configured to change that behavior, to prevent the often minute-long hangs or even crashes that result from stalled dns queries. Some Netscape Navigator versions for Unix, for example, expose this behavior. pdnsd is configurable via a file and supports run-time configuration using the program pdnsd-ctl that comes with pdnsd. This allows you to set the status flags of servers that pdnsd knows to influence which servers pdnsd will query, and the addition, deletion and invalidation of DNS records in pdnsd’s cache. Parallel name server queries are supported. This is a technique that allows querying several servers at the same time so that very slow or unavailable servers will not block the answer for one timeout interval. Since version 1.0.0, pdnsd has full IPv6 support.