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ip nat behavior on router

Hi all

Can anyone tell me what is the expected behavior of nat on a router when the inside interface is not set?

My understanding was that, in order for NAT to work an inside and outside interface needs to be defined? We have a router here in which we have defined the outside interfaces but not inside but it's still natting. I'm wondering how it chooses which interface is the inside one? or is this a bug of some sort?

Thanks all


Re: ip nat behavior on router

Data packet source address translation.

PIM control packet (PIM payload) address translation, including Auto-RP and PIM Version 2 bootstrap router (BSR).

The mstat, mrinfo, and mtrace command requests and responses.SDR advertisement or application payload.

With the above translations, PIM works in an enterprise domain even if part of the domain is behind NAT. All sources and receivers behind the NAT router can send and receive packets to the rest of the PIM cloud, and take advantage of the RP/RP mapping agent on either side of the cloud.

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