How to link Docker services across hosts?

Question

Docker allows servers from multiple containers to connect to each other via links and service discovery. However, from what I can see this service discovery is host-local. I wou

Answer 1

It is possible to bridge several Docker subnets together using Open vSwitch or Tinc. I have prepared Gists to show how to do it:

• Open vSwitch: https://gist.github.com/noteed/8656989
• Tinc: https://gist.github.com/noteed/11031504

The advantage I see using this solution instead of the --link option and the ambassador pattern is that I find it more transparent: there is no need to have additional containers and more importantly, no need to expose ports on the host. Actually I think of the --link option to be a temporary hack before Docker get a nicer story about multi-host (or multi-daemon) setups.

Note: I know there is another answer pointing to my first Gist but I don't have enough karma to edit or comment on that answer.