In #1143, @altaurog proposed a --link-host option, which I'd like to resurrect for consideration, to link to host ports, with port number rewiring. At the moment, Ambassador provides this ability, but requires forwarding through a proxy (socat). Here's an example concept for --link-host:

docker run --link-host hostip:hostport:aliasport[:hostport:aliasport:...]:alias
# where hostip is any routable IP from the host, or 127.0.0.1 for localhost

There is an alternative practice of using --add-host=alias:$(hostip), but this practice doesn't address the port rewiring that could be required.

Thanks for your consideration.