Reverse NAT

Unanswered Question

Hi All,

I've got an interesting situation trying to get NAT working properly with a Cisco ASA 5510.

The Outside interface of the ASA is set as a public routable assigned to us by our ISP. Our ISP also routes several other networks (3 class C networks) to us. What I need to do is to NAT all of the IPs in these additional subnets to one single IP on the internal network.

Some other details:

Internal Network:

Internal Host (CSS11501):

ASA Inside Interface IP:

ASA Outside Interface IP:

ASA Outside Network:

Additional Networks:,,

NB: Networks/IPs have been changed to protect the innocent.

I have tried implementing the above with dynamic NAT rules with the "real" IPs on the outside interface and a single-IP NAT pool on the inside interface, but it doesn't seem to be working.

Any pointers on how I can achieve such a setup with a Cisco ASA5510?

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Jon Marshall Tue, 06/12/2007 - 22:54
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Could you post relevant config. I would have thought the following should work

nat (outside) 1 outside

nat (outside) 1 outside

nat (outside) 1 outside

global (inside) 1 "ip address"



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