Distro yang digunakan = CentOS 5.4 (sama saja tinggal di sesuaikan)

yum install bridge-utils
vi /etc/sysconfig/network-scripts/ifcfg-br0

isinya

DEVICE=br0
BOOTPROTO=static
IPADDR=10.55.1.50
NETMASK=255.255.255.0
TYPE=Bridge
ONBOOT=yes
BRIDGE=br0

Rules Firewall

(terserah mau compile denan opsi apa)

adduser -d /dev/null -s /bin/false -g squid squid
/usr/local/sbin/ebtables -t broute -A BROUTING -p IPv4 --ip-protocol 6 --ip-destination-port 80 -j redirect --redirect-target ACCEPT
/sbin/iptables -t nat -A PREROUTING -i br0 -p tcp --dport 80 -j REDIRECT --to-port 3128