Destination NAT/PAT clarification

[MCmgt]

Prior to shooting myself in the foot I want to make sure I'm on the right track.

I have an application where I'd like to take inbound connections directed at a particular port on my untrusted "outside" FW interface and redirect them to the same port on an RFC1918-addressed host on my trusted "inside" interface. That is:

OUTfirewall:47808 -> INrinkchiller:47808

I'm looking a Understanding_NAT-4.1-RevC.pdf and it seems to point to a NAT policy like this:

This doesn't make a whole lot of sense to me. Am I on the right track or hopelessly confused? 🙂

[panos]

Hi,

Why did you choose source translation also ? I don'th think you need that.

[gswcowboy]

destination translation is for inbound traffic (out to out zone) so removing the source translation would the first step. Dest translation address object should point to your internal IP. The OUTfirewall object should also reflect the public facing IP.

[MCmgt]

Thanks! So something along the lines of this?

And finally, it just occurred to me, since I'm hiding a bunch of devices behind that same external FW IP am I asking for trouble?

[gswcowboy]

The security rule is good (outside to inside) destined for public facing IP. Inside to Outside source translation with dynamic IP/Port Src Translation for outbound traffic is a typical Src. NAT rule.