10.2. Can a FreeBSD box be used as a dedicated network router?

Internet standards and good engineering practice prohibit us from providing packet forwarding by default in FreeBSD. You can however enable this feature by changing the following variable to YES in /etc/sysconfig:

            # If you want this host to be a gateway, set to YES.
            gateway=YES
          

This option will put the sysctl variable net.inet.ip.forwarding to 1.

In most cases, you will also need to run a routing process to tell other systems on your network about your router; FreeBSD comes with the standard BSD routing daemon routed(8), or for more complex situations you may want to try GaTeD (available by FTP from ftp.gated.Merit.EDU) which supports FreeBSD as of 3_5Alpha7.

It is our duty to warn you that, even when FreeBSD is configured in this way, it does not completely comply with the Internet standard requirements for routers; however, it comes close enough for ordinary usage.