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 Job manifest at /home/laborant/batch-job.yaml is exiting with a non-zero exit status. The Job has limited retries configured. Inspect the cluster and the manifest to find the bug, fix it, and reapply.
A stubborn process is running on the system, kill it :)
A helper script that lists every container image running in the cluster — along with its on-disk size and the workload that uses it — has been downloaded to cplane-01. Install it as a kubectl plugin named kubectl-images so that kubectl images works from any directory.
Refactor a slow, single-threaded C file downloader that fetches files sequentially into a multi-threaded program using POSIX Threads (pthreads) to achieve concurrent downloads.
Write a C program that calls fork() to clone a process and execve() to execute a command, then print and retrieve the child process PID.
Compile a small C loop with -O2 -S, inspect the generated assembly, report how many add instructions gcc produced and see how much it has optimized the equasion.
Run gcc -E on a small C program and find the exact line where the preprocessor expanded a macro into a printf call.
Produce a valid ELF binary that runs and exits cleanly, but does not define a main() function.
A newly provisioned server is reachable as root with a shared seed password. Create a sudoer admin user, switch SSH to key-based access, disable password and root logins, and retire the seed credential.
An inventory service lives inside a private VPC and keeps its debugging port bound to 127.0.0.1. Use SSH local port forwarding with a jump-only bastion to query the debugging port from your workstation.
