mod_dns is an Apache module that provides
efficient and configurable hostname lookups. Its
DNS resolver timeout and retry settings are
configurable with millisecond resolution. mod_dns
is a drop-in replacement for Apache's core
"HostnameLookups On" directive. The module uses a
shared memory cache (needs EAPI+mm) to store
recently resolved hostnames. By default the cache
uses 200k of shared RAM, and will cache up to 1024
IP/host names.
