Docker Networking

Simple example of Docker networking. Creating the environment manually and with Docker Compose.

This environment is composed of a Node.js application that depends on a Mongo database, each one in a different container connected through a network.

To configure it manually

Command to create the network:

docker network create --attachable appnet

To build the Node application image run the following command:

docker build -t mongoapp .

To run the containers from the images:

docker run -d --name db mongo
docker run -d --name app -p 3000:3000 --env MONGO_URL=mongodb://db:27017/test mongoapp

And finally, to connect the containers to the network previously created, execute each of these commands:

docker network connect appnet db
docker network connect appnet app

To configure it using Docker Compose

To build the services run the following command:

docker-compose build

Command to create and start the environment:

docker-compose up -d

Command to stop and delete the environment:

docker-compose down

For more information about Docker Compose consult its documentation