>If you have a slow DNS server that is causing you delays, for example while browsing the web, then try switching to a faster DNS server.
If that does not work, then here’s a trick you may want to try: make your computer perform DNS lookups for the hostnames you use most often (such as www.google.com) on a regular basis.
On Mac OS X, Linux and UNIX systems this can be accomplished using a simple cron job, just execute a command like:
nslookup http://www.google.com
or:
This will perform the DNS lookup, and -as a side-effect- add the result to the local DNS cache.