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.
Practice authenticating to an HTTP API from the command line using both a username and password and a bearer token, and learn a couple of tricks along the way.
Practice one of the most common command-line combinations for HTTP API access: fetch a JSON response with curl and pipe it into jq to pretty print, reshape, or get only the relevant parts.
Practice calling HTTP APIs from the command line: send JSON bodies with POST, PUT, and PATCH, upload a file, delete a resource, and read the status codes the server answers with.
Learn the basics of accessing HTTP APIs from the command line: call different endpoints, read the response body, headers, and status code, follow redirects, and request an alternative representation of a server resource.
An internal service started receiving requests from unexpected IP addresses. Identify the unexpected sources and find out which workloads and teams are behind them.
An internal service started receiving requests from unexpected IP addresses. Identify the unexpected sources and find out which systems are behind them.
Practice manually resolving public domains, internal hostnames, and locally defined names to the corresponding IP addresses so you feel confident next time a DNS issue occurs.
Practice reading the network configuration of Linux hosts: find interface names, IP and MAC addresses, the default gateway, and detect which routes a server uses to reach different destinations.
The security team left five NetworkPolicy files on the workstation. Only one of them lets the frontend reach the backend while granting nothing more. Identify it and deploy it, unchanged.
The production Kubernetes cluster lives inside a private VPC, and its API server has no public endpoint. Turn an SSH connection to the bastion host into a SOCKS proxy and teach kubectl to use it, so the cluster becomes manageable from your workstation.
