Modelos de Red en Docker

What network models exist in Docker?

Exploring networks in Docker opens up a world of possibilities, especially for understanding how containers operate. Docker offers five different networking models, but one stands out as the most widely used, while the others are more appropriate for testing. This section breaks down each of these models and their applications.

What is the bridge network model?

The bridge model is the default in Docker and allows communication between containers in a local environment. This model is perfect for internal testing, where you want containers to "talk" without interfering with the outside world.

What is the host model for?

The host model allows containers to use the IP address of the host, simulating a real computer within the network. This model is efficient and resource-intensive, ideal for simulating production environments and detailed network testing.

Why isolate a container?

The isolated network model disconnects a container from the outside world, useful for testing system resilience to communication failures. This allows you to analyze the behavior of the system if one part is not operational, ideal for test environments.

How does the overlay model work?

The overlay model allows containers to communicate with each other, even if they are on different machines. It is crucial in large-scale deployment scenarios and is widely used by orchestrators such as Kubernetes.

What is the MacVLAN model?

MacVLAN assigns a real MAC address to each container, making them look like independent machines to the network. This model is useful for creating environments where each container acts as a standalone entity, providing flexibility for various configurations.

How to establish inter-container communication in Docker?

Establishing communication between containers is an essential aspect when working with Docker, and the bridge model facilitates this process. Here is a practical example of how to set up a personal network for two containers to communicate.

How to create a bridge network?

For this exercise, we start by creating a network with the command:

docker network create mi_red_bridge

This command generates a network identified by a unique set of characters.

How to download and run an Nginx container?

First, we download and run an Nginx container, assigning it to our network:

docker run -d --network my_network_bridge --name web_server nginx:latest

This command deploys Nginx in the background, inside the bridge network.

How to run a client with a Linux terminal?

To interact, we need another container that will act as a client:

docker run -it --network mi_red_bridge --name client alpine:latest /bin/sh

Alpine provides a lightweight terminal to run test commands.

How to establish communication between the containers?

On the client, we install 'curl' to test the communication:

apk add --no-cache curl

Then, we use 'curl' to access the web server:

curl http://servidor_web

This shows the home page of the Nginx server from the client, confirming the communication between both containers via the bridge network.

Recommendations for practicing with networking in Docker

Playing with network configurations in Docker is an excellent way to learn and better understand the behavior of containers in different environments. We encourage you to experiment with all network models to determine which one best suits your projects. This practice not only enriches your knowledge, but also empowers your skills to face real challenges in production environments. Don't stop and keep learning!