Cisco 837 / iOS 12.4 / How to do Source and Destination NAT at the same time?

[rsacherer2]

Hello,

I have 2 ADSL Lines connected with two Cisco 837 Routers, and I need incoming port-forwarding. But it seems that I am unable to configure the router to do not only incoming destination NAT but at the same time also Source NAT so that the outgoing packages will be sent to the same router where the incoming connection originates from and not to the router defined by the current default gateway.

I also can not depend on an IP (dynamic IP's) so I would need a solution which uses the interface (dialer) instead of an configured IP.

Thanks,
Best,

[Federico Coto Fajardo]

Hi,

On IOS devices you can NAT both the source and destination of the packets but not in a single statement (I believe).

i.e.

To NAT the source:

ip nat inside source...

To NAT the destination

ip nat outside source...

So, you might be able to accomplish what you need, but using two statements what do you think?

Federico.

[rsacherer2]

Hi,

I have currently no direct access to the device, but as far as I remember the nat outside source did not let me configure an interface, just an IP and that would not cut it as we have dynamic ips ... but i will check again, it would be great if you have any more specific information though ...