Routing with external interface doesn't work after a while

[Joe]

Erik Norgaard wrote:
> There is some trick to handle that, IIRC something like this would do:
> 
> ext_if=fxp0 # external interface
> nat on $ext_if from <lan>  to !<lan> -> ($ext_if)
> 
> The () means that pf will lookup the ip on that interface, and update 
> dynamically when the ip changes.
>
That is correct.