The /etc/hosts file is where you put the name
and IP address of local hosts. If you place a host in this file, then you
do not need to query the domain name server to get its IP Address. The
disadvantage of doing this is that if the IP address for that host
changes, you must keep this file up to date yourself . In a well managed
system, the only hostnames that usually appear in this file are an entry
for the loopback interface, and also the local hosts name. By default:
127.0.0.1 localhost 192.168.1.254 firewall
Do not forget to declare the internal address(es) of a ssh client in this file if you want to connect quickly to your firewall machine!