Challenge on ,
Connect a Container to a Service Running on the Docker Host
Learn how to access services running on the Docker host from a bridge-networked container, without hardcoding host IP addresses or disabling network isolation.
Challenges
Focused, hands-on DevOps and server-side problems with hints, feedback, and automated solution checks.
Challenge on ,
Redirect a Container's Requests Without Modifying the App
Sometimes you need an app to talk to a different backend, but its configuration is unknown or the destination address is hard-coded. Practice overriding hostname resolution for a single Docker container to redirect its requests without modifying the app or rebuilding its image.
Challenge on ,
Docker 101: List Docker Networks and Inspect the Default Bridge
Explore the container networks of a freshly installed Docker host: find the default network, its subnet and gateway, and the Linux interface behind it.
Challenge on , ,
Docker 101: Publish a Redis Container Port on a Private IP Address
A common setup for small deployments: two servers (VM or bare-metal), each with a public and a private IP. The app listens on the public port but wants to talk to Redis over the private network. Can you set it up?
Challenge on ,
Docker 101: Reach a Container Without Publishing a Port
Practice accessing a containerized service directly from the Docker host using its IP address.
Challenge on ,
Docker 101: Publish a PostgreSQL Container Port on Localhost Only
Learn how to keep a database available to an app running on your workstation without exposing its port to other machines on the network.
Challenge on ,
Docker 101: Publish a Container Port to Access the App from the Host
A web app is listening inside a container, but the browser can't reach its IP address. Recreate the container so the app is available on port 80 of the Docker host.
Challenge on
List All Tags in a Container Repository
Practice discovering what has been published to a remote container repository by listing its tags using crane, regctl, or a direct call to the registry HTTP API.
Challenge on ,
Customize nginx Startup Behavior with a postStart Lifecycle Hook
by Omkar Shelke
Create a Pod that uses a postStart lifecycle hook to write a custom message to the nginx welcome page, expose it via a NodePort Service, and verify the hook ran successfully.
Challenge on
Docker 101: Authenticate to Private Container Registries
Practice using docker login to authenticate against multiple private container registries with different credentials, then pull and push images across them.