#!/bin/bash

BR="/usr/sbin/brctl"
IF="/sbin/ifconfig"

$IF eth1 0.0.0.0
$IF eth2 0.0.0.0
$IF eth3 0.0.0.0

$BR addbr br0
$BR addif br0 eth1
$BR addif br0 eth2
$BR addif br0 eth3

$IF br0 192.168.1.1 netmask 255.255.255.0