NAT Question

NightShade03

I understand NAT and how it works although there is one thing that has me confused. The book question is "Any request on any port from the inside global address must be forwarded to the internal web server. The internal web server is 192.168.1.50 and the inside global is 5.1.1.10".

A: ip nat inside source static 192.168.1.50 5.1.1.10

What I don't get is the source part. Does source just mean that any "Source" coming from the inside global address just gets forwarded to the internal web server?

NOTE: The question doesn't specify ports which is what may be throwing me off.

sandman748

Correct me if I'm wrong here but does this command not statically map that internal ip address to the ip address of the outgoing interface? Therefore anything going out from 192.168.1.50 would become 5.1.1.10 and anything coming in on 5.1.1.10 is translated back to 192.168.1.50.

The source part of the command indicated whats coming into the router. In this case a static ip address being 192.168.1.50 but it could also be used to reference an ACL

e.g. ip nat inside source list 10 - would reference any ip addresses included in ACL 10