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New Member

Problem with WAN connection

Any help with this would be appreciated.

About my network:

I have a 1604 with T1 card. This is hooked up to my ISP on the T1, and hooked up via 2 channel ISDN on the BRI port to a remote warehouse we have. Currently, I have a Shiva VPN Gateway that I use to do NAT and connect my internal network to the internet. It has one adapter on the local network and one adapter on the network that connects to the router.

I currently have incoming NAT set up on the firewall so that any traffic coming to an internet IP from the network at our warehouse will be passed through the firewall to a machine on the local network.

Here is my problem:

I need every machine at our warehouse to be able to access every machine at our plant here. TO do this, I would have to create a NAT entry in the firewall for every machine in the plant, and I dont have that many internet IPs.

I would like to be able to connect the hub that carries the internet traffic (hub between the VPN and the router) to one of the other switches in the building. This would mean that every ethernet port in the building could be on either our internal network or have a real internet IP.

This is going to require adding a second IP to the E0 port of the router. I have figured out that you can use a "secondary" after the ip address ... command, but I am not fully sure of what that will do.

Short of getting another router for the ISDN connectivity and putting it on the local network, can anyone suggest a way of doing this.

If I did it the way i suggested, both IP networks through the whole network, is this secure? I will be putting access lists on the router once I get it working.

If you need clarification or want more information, please let me know. I can be reached via email at

Thanks in advance for your help.


New Member

Re: Problem with WAN connection

I don’t know that I could recommend you try to make a loop around your firewall/VPN box… kind of defeats the purpose. Adding a secondary IP address to the router will make both networks routable but you can still only have one gateway on the network. And would you be putting a second NIC in each of the PC’s? That could get ugly too. I think if I were you I’d go over this with a Cisco designer to see if they can come up with a viable solution for your needs.