Docker Networking: Auto-discovering host names in a bridge network

Question

I am trying to get the following pretty basic (or so I thought) networking setup to work using Docker 1.9:

• I have multiple containers that run services, e.g. a

Answer 1

docker 1.10, and PR 19242 can help:

docker create --net-alias=[]: Add network-scoped alias for the container

docker 1.10 has a new section Network-scoped alias:

While links provide private name resolution that is localized within a container, the network-scoped alias provides a way for a container to be discovered by an alternate name by any other container within the scope of a particular network.
Unlike the link alias, which is defined by the consumer of a service, the network-scoped alias is defined by the container that is offering the service to the network.

Continuing with the above example, create another container in isolated_nw with a network alias.

$ docker run --net=isolated_nw -itd --name=container6 --net-alias app busybox
8ebe6767c1e0361f27433090060b33200aac054a68476c3be87ef4005eb1df17

Now let us connect container6 to the local_alias network with a different network-scoped alias.

$ docker network connect --alias scoped-app local_alias container6

container6 in this example now is aliased as app in network isolated_nw and as scoped-app in network local_alias.