How to Use Docker Health Checks

Docker health checks allow you to monitor the health of your running containers. This article explains how to set up and use Docker health checks.

Defining a Health Check in Dockerfile

Add the following lines to your Dockerfile to define a health check:

FROM nginx
HEALTHCHECK --interval=30s --timeout=10s \
  CMD curl -f http://localhost/ || exit 1

Building and Running the Container

Build the Docker image:

docker build -t my_nginx_health .

Run the container:

docker run -d --name my_nginx_container my_nginx_health

Checking Container Health

View the health status of the container:

docker ps

Inspect the container for detailed health information:

docker inspect --format='{{json .State.Health}}' my_nginx_container

Conclusion

Docker health checks provide a simple way to monitor the health of your containers, ensuring that your applications are running as expected.