Docker networks

A Docker network is a layer that provides runtime isolation for containers. It is a kind of sandbox in which to run containers that are isolated from other containers. When the Docker is installed, by default it creates three networks that should not be removed. These three networks are as follows:

• bridge
• none
• host

Also, Docker provides the user with an easy way to create your network. For this purpose, Docker offers two drivers—bridge and overlay.

Bridge can be used for the local environment, and it means this kind of network is allowed on a single host. It will be useful for our applications because it promotes isolation between containers regarding security. This is a good practice. The name of the container attached to this kind of network can be used as a DNS for the container. Internally, Docker will associate the container name with the container IP.

The overlay network provides the ability to connect containers to different machines. This kind of network is used by Docker Swarm to manage the container in a clustered environment. In the newest version, the Docker Compose tool natively supports Docker Swarm.