Docker Custom Bridge Networks

Custom bridge networks are one of the most useful Docker networking features for beginners.

They let related containers communicate with each other by container name. This makes multi-container setups cleaner than using the default bridge network.

Create a custom network

docker network create app-network

Check it:

docker network ls

Run containers on the network

Start a database container:

docker run -d --name database --network app-network mysql:8

Start an app container on the same network:

docker run -d --name api --network app-network my-api:1.0

Now api can reach the database using the hostname:

database

Docker provides name resolution inside the custom network.

Why custom networks are better

Custom bridge networks are better for app setups because:

• Containers can find each other by name
• Related containers are grouped together
• Network setup is easier to inspect
• You avoid hard-coding container IP addresses
• It feels closer to Docker Compose and production-style setups

Inspect a network

docker network inspect app-network

This shows containers connected to the network and their assigned IP addresses.

Connect an existing container

You can connect a running container to a network:

docker network connect app-network container-name

And disconnect it:

docker network disconnect app-network container-name

Remove a network

After removing containers, remove the network:

docker network rm app-network

Docker will not remove a network if containers are still attached.

Simple mental model

Use a custom bridge network when containers belong to the same application.

app-network
-> api container
-> database container
-> cache container