Docker — Container Network Basics

A little container knowledge every day!

As a K8s administrator, understanding the fundamentals of Docker container networking is crucial, as containers form the underlying bedrock for K8s.

What is Docker Container Networking?

Docker container networking enables communication between Docker containers, and between Docker containers and external networks. It’s the system that bridges the gap between isolated containers, allowing them to function as coordinated services.

The following are different network “modes” used when working with containers:

None Mode

In the None networking mode, the container doesn’t have any networking access. This mode is suitable for containers that don’t require any network connectivity. For example, you might have a container that performs some local data processing or computation.

# Run a container with no network
$ docker run --network none alpine

Bridge Mode

The Bridge networking mode sets up a private internal network within the host for the container to operate within. Containers within this network can freely communicate with each other. However, if they need to interact with external…