Docker 101: Pull a Container Image by Digest
Practice pulling a container image using an immutable digest reference instead of a mutable tag.
Focused hands-on problems designed to help you hone your DevOps or Server Side skills. Some challenges are more educational, while others are based on real-world scenarios. The platform provides hints and feedback for each challenge, including automated solution checks.
Challenges crafted by iximiuz Labs to help you master DevOps and Server Side topics.
Practice pulling a container image using an immutable digest reference instead of a mutable tag.
Pull container images using the 'docker pull' command and explore how the image name determines its source registry and repository.
Learn how to keep your container images lean by excluding development dependencies (linters, test frameworks, etc.) from the production build.
Practice installing OS-level packages during a Docker image build to satisfy system library requirements of your application.
Learn the absolute basics of Dockerfile authoring by containerizing a simplistic Node.js server application with just three instructions: FROM, COPY, and CMD.
Learn how to write a Dockerfile from scratch and build a working container image for a web server application with a simple set of dependencies.
Practice pausing and resuming a running container: start a resource-hungry container, pause it, inspect its state, and then unpause it back to life.
Practice using UNIX signals with containers for controlling application behavior: Send a SIGUSR1 to a containerized app to trigger its memory usage reporting.
Learn how to configure the restart policy for a container so that it restarts automatically on application failure.
Practice listing containers and inspecting their state to identify running, exited, and crashed applications - a vital skill for day-to-day operation of containerized systems.