Flushing DNS

When accessing websites or mailservers, your DNS resolver caches the request so that future lookups are fast. However, sometimes when a zone on DNS is being changed while you work, you want to be able to clear the cache to force the resolver to get the latest name:IP address pair mappings. What to do about this?

Here are some command line commands for flushing the DNS cache on your local machine:

Flush DNS on OS X
rcogley@RickMBP-Tiger ~ % lookupd -flushcache
rcogley@RickMBP-Leopard+ ~ % dscacheutil -flushcache
Flush DNS on Windows
rcogley@win01 $> ipconfig /flushdns