Docker Network

By default, all containers are connected to a virtual network bridge create by docker. They can access each other by IP address. However, the IP address is not fixed and may be different each time the container is started.

Docker provides us a way to use container names instead of IP address.

Common Docker Network Commands

  • docker network create: create a network
  • docker network ls: check all networks
  • docker network rm: remove a network
  • docker network inspect: check details of a certain network
  • docker network prune: clear unused local networks
  • docker network connect: add a container to a certain network
  • docker network disconnect: remove a container from a network
  • docker network --help

Usage with Examples

To connect a existing container to a network:

docker network create myNetwork
docker network connect myNetwork mysql
docker inspect mysql

Now you should see two items under network.

To connect a container to a network when creating the container

docker run -d --name nginx2 -p 80:80 --network myNetwork nginx
docker inspect nginx2

There should be only one item under network. The container will not be connected to the default network.

After executing the commands above, you can use container names just like localhost to access containers under the same (custom) network.

ping mysql