Docker Networks
Purpose
Docker networks allow containers to communicate with each other while remaining isolated from other containers and the host system.
Networks in Use
| Network | Purpose |
|---|---|
| bridge | Default Docker network |
| compose-practice_default | Docker Compose nginx lab |
| gitea_default | Gitea service |
| npm_default | Nginx Proxy Manager |
| portainer_default | Portainer |
| uptime-kuma_default | Uptime Kuma |
Observations
Each Docker Compose stack automatically creates its own network.
Examples:
| Service | Container IP |
|---|---|
| uptime-kuma | 172.17.0.2 |
| compose-practice-nginx-1 | 172.18.0.2 |
| gitea | 172.19.0.2 |
| npm | 172.20.0.2 |
| portainer | 172.21.0.2 |
Commands
View networks:
docker network ls
Inspect a network:
docker network inspect NETWORK_NAME
Example:
docker network inspect gitea_default
Lessons Learned
- Every Compose stack gets its own network.
- Containers communicate using private Docker IP addresses.
- Containers on separate networks cannot automatically communicate with each other.
- Docker networks provide isolation and security.
- Reverse proxies often require containers to share a network.
Date Created
June 15, 2026