What you are learning
Runbrace is turn diagnosis into a reusable runbook. The teaching focus is Runbooks (severity, checks, rollback, comms).
Work in order. Early parts set vocabulary and environment; later parts assume the earlier checkpoints.
How to use these lessons
Read the goal, open the matching GitHub folder, complete the lab or exercises, then return for the explanation. If a command fails, check you are in the numbered folder first.
Parts in order
Each chapter below is one checkpoint in this lab.