WRT54GL Linksys Routers

Introduction

Things I have done with a WRT54GL router running ddwrt custom firmware:

• Single router with 2 subnets each with seperate vlan, IP block, DHCP server, and firewall rules.
• VLAN trunking
• QoS traffic prioritization based on IP address
• WPA encrypted wireless point to multipoint bridging

Things I may implement in the future:

• Multiple wireless networks on the same router with different SSIDs and different vlan tags

Details

Adding a third vlan and network

These steps assume you already have two other vlans configured.

Add ports to the new vlan

nvram set vlan4ports="0t 5t"
nvram commit

Create a startup script to load firewall rules and configure the interface

echo '
#!/bin/ash
PATH="/sbin:/usr/sbin:/bin:/usr/bin:${PATH}"
iptables -I FORWARD -i br0 -o vlan4 -j ACCEPT
iptables -I FORWARD -i vlan4 -o br0 -j ACCEPT
iptables -I FORWARD -i vlan4 -o vlan1 -j ACCEPT 
iptables -I INPUT -i vlan4 -j ACCEPT  
ip addr add 10.7.1.7/24 brd + dev vlan4 
ifconfig vlan4 up
' > /jffs/etc/config/vlan4.startup  
chmod 750 /jffs/etc/config/vlan4.startup