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Ip nat insiside / outside onthe SAME interface

Hello friends. I have a router 805 with 1 ethernet and 1 serial interface. I'm trying to use the ethernet like a wan connection because my ISP give me the access to Internet through an ethernet cable. I have 2 valids IP's, one is in the ISP and the other on my router. In the ethernet on my router I would like to put de public and private ip. With my private block I want to configure a Nat Pool ant try to access to Internet. Can i do this? Can I use the same interface ethernet like wan and lan conecction through Nat? Can i use a logical interface to simultae the "ip nat inside" or "ip nat outside" interface?

Please, your help. Than you very much for your attention.


Charlie K.

  • Other Network Infrastructure Subjects

Re: Ip nat insiside / outside onthe SAME interface


I dont think its possible/doable with the kinda setup you have.

You need to have 2 interfaces to get inside and outside nat commands configured.

As always you can make use of using a logical interface but still you need to give some kinda reachability to that logical interface.

which you can have only with one of ur interface configured & connected to the public world..