Enhance --link to connect to host's networks, and rewire ports

[dhbaird]

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.

[cades]

+1

[cusspvz]

+1

[lynchc]

+1

[chiavegatto]

+1

[thaJeztah]

Not sure if this is going to be part of that (yet), but with the 1.7 release, there will also be "experimental" builds, to allow testing future features.

With the integration of libnetwork in Docker 1.7, there's work in progress for a Network-API, see this pull request for what's being worked on; #13441

[thaJeztah]

I asked a maintainer of libnetwork if this scenario will be supported with the coming features and he added some additional information in a comment; #13441 (comment)

[mavenugo]

Thanks @thaJeztah . I would recommend opening an issue in libnetwork & if there is enough interest, this feature can make it to appropriate drivers (inbuilt or external)

[LK4D4]

links is not a way to make containers talk to each other now.