Flush DNS cache in Lion and Mountain Lion

To flush the DNS cache in Mac OS X 10.5 and 10.6, run this command in Terminal:

sudo dscacheutil -flushcache

To do the same in 10.7 and 10.8, run this command:

sudo killall -HUP mDNSResponder

—
http://nerdlogger.com/category/cli/

http://hints.macworld.com/article.php?story=20120808001623238