Flush DNS Cache on MAC OS X

Mac OS X - Clearing or flushing the DNS Cache

Once you go to a Web site, or do any DNS lookup, the IP gets cached for quite a while. This becomes a royal pain if you’re a systems administrator who is in the middle of migrating domains from one server to another. Executing the following clears the cache, restarts the caching daemon, and fetches fresh DNS records. And there was much rejoicing…

For Leopard


sudo dscacheutil -flushcache


For Tiger

lookupd -flushcache

(On Windows you do ipconfig /flushdns)