The basic firewall configuration begins with connecting the pfSense® appliance to the Internet. The pfSense appliance should be unplugged at this time.
Connect one end of an Ethernet cable to the WAN port (shown in the Input and Output Ports section) of the pfSense appliance. The other end of the same cable should be inserted into a port of the Cable or DSL modem. The modem provided by the ISP should have multiple LAN ports. Any port should work.
Next, connect one end of a second Ethernet cable to the LAN port (shown in the Input and Output Ports section) of the pfSense appliance. Connect the other end to the computer.
The default IP Address on the LAN subnet on the pfSense firewall is
192.168.1.1/24. The same subnet cannot be used on both WAN and
LAN, so if the default IP address on the ISP-supplied modem is also
192.168.1.1/24, disconnect the WAN interface until the LAN
interface on the firewall has been renumbered to a different
subnet (like 192.168.2.1/24).