Edit this file /private/etc/hosts.

Terminal

$ sudo nano /private/etc/hosts

##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##
127.0.0.1       localhost
255.255.255.255 broadcasthost
::1             localhost
fe80::1%lo0     localhost
127.0.0.1       mkyong-mac
198.x.x.x       linode-bot1
1.2.3.4         www.google.com

References

  1. What is the difference between /etc/hosts and /private/etc/hosts
  2. Modify your hosts file