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I've been searching far and low to try and get this configuration working.

All I want to do is configure my asus rt-n66u router running ddwrt to isolate port4 from my private network, yet have internet access on it.

Doing this on a wrt54gl running dd-wrt was easy but my rt-n66u doesn't seem to like this setup as much. I can get as far as having the device on port 4 get an ip address from the secondary dhcp server, but no internet access. strangely enough i also seem to be able to ping the 'private' devices but not

Any advice would be truly appreciated!

Info: My router IP Address is, DHCP Server is ON. PPPoE connection to the internet.

Configuration Screenshot 1

Configuration Screenshot 2

EDIT: I am unable to add additional screenshots.

dhcpd is ON for vlan3, range:

firewall config is as follows:

iptables -I FORWARD -i vlan+ -o vlan+ -j DROP

iptables -I FORWARD -i vlan+ -o vlan2 -j ACCEPT

iptables -I FORWARD -i vlan2 -o vlan+ -j ACCEPT

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