Docker Machine Router

This tool allows you to assign an chosen ip address that is visible from the OS X host to your containers.

Installation

curl -L https://github.com/fntlnz/docker-machine-router/releases/download/v0.2.1/docker-machine-router > /usr/local/bin/docker-machine-router
chmod +x /usr/local/bin/docker-machine-router

Usage

Docker machine router relies on the DOCKER_HOST environment variable as the Docker client does.

You can export that variable using the docker-machine env <machine-name> command.

MACHINE=dev
eval $(docker-machine env $MACHINE)

Now that all's ready you can create the routes by invoking docker-machine-router. The -E option, tells sudo to get all the environment variables.

sudo -E docker-machine-router

Options

cidr:

This is the Class Inter-Domain Routing that docker-machine-router will use to create its routes.

The default cidr is 10.18.0.0/16 you can change it using the -cidr option:

sudo -E ./dist/docker-machine-router -cidr="10.20.0.0/16"

The default cidr: 10.18.0.0/16 allows allocation of ip addresses in the 10.18.0.0 - 10.18.255.255 range, for a total of 65536 addresses.

Start a container using the dmr network and assigning a custom IP.

Here we are starting a container using the nginx image and the dmr network (The one provided by docker-machine-router).

Our container will have two ip addresses, one exposed to the OS X host 10.18.241.100 and one exposed only inside the VM 127.0.241.100

Note that the ip exposed only in the VM (127.0.241.100)is needed in order to allocate multiple 80 ports on the docker network.

docker run --net dmr --ip 10.18.241.100 -p 127.0.241.100:80:80 -it nginx

The Same with docker-compose

docker-compose.yml

version: "2"
services:
  web:
    image: nginx
    ports:
      - "127.18.20.20:80:80"
    networks:
      dmr:
        ipv4_address: "10.18.20.20"
networks:
  dmr:
    external: true

This is the equivalent of what we did with the run command.