To complete this step, start a nginx container which binds directly to port 80 on the Docker host using default host network by using --network host.

Protip

You can verify that the container is bound to PORT 80 by running curl docker:80

In this example, we're going to start by creating new network my-network. We will use this network to attach multiple containers

Task

To complete this step, create a custom network named my-network using docker command.

A app.py file has been created for you You can view contents of file by cat app.py

Task 1 : Create Dockerfile

To complete this task, you need to copy the following code:

FROM python:3.4-alpine
WORKDIR /flask
COPY app.py /flask
RUN pip install flask redis
CMD ["python", "app.py"]

Task 2 : Build Docker Image

To complete this step, use the docker build command to build the image. You can give the image a name redis-flask-example by using the -t option.

In this step, we will run a flask application that communicates with our existing Redis instance.

Task

Running following command to run redis container and attach to custom network my-network created in the first step docker run -d --name=redis --net=my-network redis

Similarly, launch the web server using the flask image and attach to the same network. So, it will be able to communicate with our Redis instance. Also, use -p 5000:5000 parameter to map ports.

Protip

You can verify that the containers are communicating by selecting Dashboard and clicking reload icon. This dashboard is connected to Port 5000 of the docker host.

Run docker inspect command to list containers attached to particular network docker network inspect my-network

Task

To complete this step, disconnect redis container from our custom network my-network