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Docker 101: Pause and Unpause a Containerized Application
Practice pausing and resuming a running container: start a resource-hungry container, pause it, inspect its state, and then unpause it back to life.
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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.
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.
Practice sending binary data to a containerized CLI tool - a helpful scripting pattern you'll often find in CI/CD pipelines and other automation jobs.
Some container images include more than one executable file, and you may want to run a container using other than the default command and/or pass some arguments to it. Learn how to do this by solving this challenge.
Practice starting containers in "detached" mode, leaving them running in the background, reading their logs, and re-attaching to them.
Run a few containers from local and Docker Hub-hosted images and experience the most typical use cases of the foreground 'docker run' command.