Forwarding The forwarding rules control which packets will be forwarded by the firewall. In addition, our forwarding rules must take care of masquerading. Once again, we start by denying everything, before explicitly allowing some sorts of traffic. Accounting The accounting rules are used to build up packet and byte counts for selected traffic. There is a single set, used for both incoming and outgoing traffic.
Every packet is checked against each rule, and the counts of ea ch matching rule incremented.
Now, ipfwadm controls accounting with the -A option. Where we assume that a machine on the local network with address 192.168.1.2 hosts the Web server. This article has shown you how to set up a Linux box as a combined router and firewall, using the network capabilities built in to the Linux kernel. For further information, a good starting p oint is Linux Journal Firewall Resources Author Biography Paul Dunne is a writer and consultant who specialises in Linux. He has a home page that describes in more detail what he does.