Capstone labs · Lesson 8 of 18 · 8 minutes

Capstone incident runbook

Write an incident runbook from gathered evidence.

Open the lab Course map

Mastery 0/3Run itExplain itApply it

learner@clairos:~ $

↑ history · Tab complete · Ctrl+C cancel · Esc, Tab to leaveExit 0

Your objectives

Hints are always available. Wrong turns never cost XP.

1
Write capstone runbook
Run nano lab/capstone-runbook.md. Save a nonempty note using the worked example below. Required evidence: status=reviewed; evidence=recorded; rollback=ready.
Hint & worked example
Edit a virtual text file using the browser editor and explicitly save it.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
nano lab/capstone-runbook.md
```
Save this example in the editor:
```
# Capstone incident runbook
status=reviewed
evidence=recorded
rollback=ready
```
Remember: Opening the editor does not complete a write task. Save and verify the contents.
2
Search reviewed marker
Run grep reviewed lab/capstone-runbook.md.
Hint & worked example
Select input lines that match a pattern; -i ignores case, -n adds line numbers, and -v inverts selection.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
grep reviewed lab/capstone-runbook.md
```
Remember: No matches is exit status 1, which is different from a malformed invocation.
3
Read capstone runbook
Run cat lab/capstone-runbook.md.
Hint & worked example
Read one or more files to standard output without editing their contents.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
cat lab/capstone-runbook.md
```
Remember: Reading a source file should precede changing it; avoid printing real secrets.

Understand the pattern

Junior operators build confidence by gathering evidence before changing systems.

nano: Edit a virtual text file using the browser editor and explicitly save it.
Opening the editor does not complete a write task. Save and verify the contents.
grep: Select input lines that match a pattern; -i ignores case, -n adds line numbers, and -v inverts selection.
No matches is exit status 1, which is different from a malformed invocation.
cat: Read one or more files to standard output without editing their contents.
Reading a source file should precede changing it; avoid printing real secrets.

Worked example and expected result

$ nano lab/capstone-runbook.md

Opening simulated nano for /home/learner/lab/capstone-runbook.md. Save or cancel in the browser.

Exit status: 0. The command completed successfully in the training fixture.

$ Save the editor buffer

# Capstone incident runbook
status=reviewed
evidence=recorded
rollback=ready

Exit status: 0. The command completed successfully in the training fixture.

$ grep reviewed lab/capstone-runbook.md

status=reviewed

Exit status: 0. The command completed successfully in the training fixture.

$ cat lab/capstone-runbook.md

# Capstone incident runbook
status=reviewed
evidence=recorded
rollback=ready

Exit status: 0. The command completed successfully in the training fixture.

Try a variation

Repeat this workflow in the sandbox with a different scratch filename. Keep the system fixtures unchanged and compare the observed output with your expectation before moving on.

Explain it

In “Capstone incident runbook”, which interpretation is safe?No matches is exit status 1, which is different from a malformed invocation.A command appearing in history proves it completed successfully.A successful first check guarantees that every dependent service is healthy.

Apply it elsewhere

Before adapting the grep workflow from “Capstone incident runbook” to another server, what should you do?Paste the training paths unchanged into production.Skip output inspection whenever the command is familiar.Confirm the current directory, target identity, permissions, and the installed command behavior first.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Capstone hardening review Try an incident drill

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