Execute Host Commands Inside a Running Container
Leverage your knowledge of Linux namespaces to reach an application's internal debug interface without installing anything into the container.
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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.
Leverage your knowledge of Linux namespaces to reach an application's internal debug interface without installing anything into the container.
Learn how to run multiple Docker containers sharing the same PID, IPC, and network namespaces - a foundation of many advanced container use cases, including Kubernetes Pods construction and container debugging tools.
Practice pausing (freeze) and resuming (thaw) a resource-hungry Linux process using the cgroup v2 freezer mechanism.
Practice using UNIX signals with containers for controlling application behavior: Send a SIGUSR1 to a containerized app to trigger its memory usage reporting.
Your Docker host has been in use for a while. Anonymous and named volumes piled up, disk space is tight, and it's time to clean stuff up.
Practice mapping existing directories to new paths using Linux bind mounts and see the core tech behind container volumes in action.
Discover why host environment variables aren't visible to containers and how to properly pass them to containerized applications in Docker.
Learn when to use the -t flag in 'docker run' to allocate a pseudo-TTY (terminal) for containers, enabling terminal-specific features like cursor control, colors, and signal handling.
Create two partitions on a blank disk: one smaller ext4 for service logs and the rest btrfs for service data. Mount both and prove they work.
Practice creating a fresh GPT partition, formatting it as ext4, and mounting it on the filesystem tree.