Focused, hands-on problems for sharpening your DevOps and server-side skills. Some teach specific concepts while others mirror real-world scenarios. Every challenge includes hints, feedback, and automated solution checks.
A new service needs to run in your development environment, but the port it requires is already in use by another app that has to keep working. Diagnose the conflict, free the port without taking the other app down, and get both services running side by side - a realistic exercise in untangling local port conflicts.
Configure systemd to keep a TCP port open at all times while starting the backing service process only when the first connection arrives.
Configure systemd to keep a Unix domain socket open at all times while starting the backing service process only when the first connection arrives.
Make a single echo server listen on either a TCP socket or a Unix domain socket, selected by its command-line argument. The challenge illustrates that the same stream-socket workflow works with two address families (AF_INET and AF_UNIX).
Write a TCP client to hold a back-and-forth conversation with a "chat" server: send a line, read the reply, send another line - repeat until the session is over. A hands-on lesson in designing an application protocol on top of a byte-oriented TCP stream.
Write your first TCP client for a push-only telemetry server that starts sending sensor readings as soon as you connect. Likely the easiest way to get started with TCP socket programming.
The Hello World of network programming: implement a tiny TCP echo server in the language of your choice.
Test your Linux and Networking skills by identifying which port a service is using. Sounds easy? Perhaps, but be careful - you only get one shot!
Test your Linux and Networking skills by pinpointing a process that is listening on a given port. Sounds easy? Perhaps, but be careful - you only get one shot!
Be a networking Sherlock Holmes - find out which port a Kubernetes app uses and send a request to it.
