dnshistory provides a means for storing a history
of DNS/name changes over time from the IP
Addresses gathered from within Web log files. At
its simplest, it will do massively parallel name
lookups very quickly. The lookups are not DNS
only, and will use whatever naming services your
system is configured with. A second mode will take
a Web log file and replace the IP addresses with
the previously stored names, sending the resulting
output to STDOUT.
