IPtables with multiple networks

hall-2k · 01-05-2010, 12:07 AM

Im someone new to linux and iptables, and im still trying to wrap my head around how it works.

Im trying to setup a gateway server, I am running CentOS 5.

Network Information;
eth0 – WAN/Public
eth1 - Spare (Future DMZ)
Bond0 (10.0.0.1 – Admin Vlan, eth2 & eth3)
Bond0.2 (192.168.55.10 – VoiceVlan, does not need internet access)
Bond0.3 (10.0.1.1 – Public Hotspot)
Bond0.4 (10.0.2.1 – Private Network A)
Bond0.5 (10.0.3.1 – Private Network B)

At the moment, I can be on any network and ping ip address and see other computers.

How do I write the iptables so that each network can access the internet but that each network can’t communicate with each other?

datopdog · 01-05-2010, 06:53 AM

Code:

iptables -P FORWARD DROP
iptables -A FORWARD -i Bond0* -o eth0 -j ACCEPT
iptables -A FORWARD -i eth0 -o Bond0* -m state --state ESTABLISHED,RELATED -j ACCEPT