Challenge, Medium, on
Start a systemd Service on the First Connection (TCP Socket Edition)
Configure systemd to keep a TCP port open at all times while starting the backing service process only when the first connection arrives.
Challenges
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.
Official Collection
Challenges crafted by iximiuz Labs to help you master DevOps and Server Side topics.
Challenge, Medium, on
Start a systemd Service on the First Connection (Unix Socket Edition)
Configure systemd to keep a Unix domain socket open at all times while starting the backing service process only when the first connection arrives.
Submissions: 17/25
Make One Echo Server Work with Both TCP and Unix Sockets
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).
Submissions: 9/23
Write a TCP Client for a Chat Server
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 a TCP Client for a Telemetry Server
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.
Write a TCP Echo Server From Scratch
The Hello World of network programming: implement a tiny TCP echo server in the language of your choice.
Challenge, Hard, on
Purge an Accidentally Pushed Image From a Container Registry
Sometimes an image needs to be removed from a registry - because it was pushed by mistake, contains sensitive data, or simply should no longer be available. Practice purging a container image properly: remove the tag, trace it to the manifest and blobs behind it, and make sure the image can no longer be pulled - even by digest.
Submissions: 30/84
Challenge, Easy, 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.
Submissions: 46/65
Secure a Container Registry with Authentication and TLS
Set up your own OCI-compatible container registry with username/password authentication and HTTPS - the kind of protection you'd expect before using a registry in production.
Submissions: 23/40
Challenge, Medium, on
Run Your Own Container Registry
Stand up a self-hosted container registry so you can push and pull images without relying on a third-party registry. Useful for tests, internal services, air-gapped environments, or just for poking at the OCI Distribution API.
Submissions: 26/40