Linux Desktop Hacks

Build a Custom Firewall Computer #81

Chapter 9, Administration and Automation

|

249

HACK

When you access the web interface, you are asked for the administrator

password for the machine (which you created when you installed Smooth-

Wall) and then you can configure it. Within the web panel is a huge range of

options and features that you can configure. These options are grouped into

categories which are visible at the top of the page.

If you need to do something that is not accessible in the web interface, you

can use the included Java SSH applet to log in to the machine and type in

commands to an SSH shell.

Enable Port Forwarding

A common requirement when running a network of machines is the need to

have a connection from outside the firewall serviced by a machine inside the

firewall (usually in the DMZ). This is the scenario for those who run a web

or email server and need to have the relevant ports accessible to the outside

world. When a computer connects to your IP address/domain, the first com-

puter that receives the connection is the firewall. Because it is unlikely you

are running a web or email server on the firewall itself (if you are, you really

shouldn’t be because bugs in these programs can compromise the security of

the firewall) you need a method to get that request to the computer that can

handle it. This is where port forwarding comes in. Its purpose is to take the

request for a service ...