Capstone labs · Lesson 5 of 18 · 8 minutes

Capstone permission audit

Audit SSH, web, and private note permissions.

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
Inspect SSH key
Run stat ~/.ssh/authorized_keys.
Hint & worked example
Inspect a file or directory metadata record, including ownership, permissions, and size.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
stat ~/.ssh/authorized_keys
```
Remember: Metadata and file contents answer different questions.
2
Inspect web file
Run stat /srv/www/index.html.
Hint & worked example
Inspect a file or directory metadata record, including ownership, permissions, and size.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
stat /srv/www/index.html
```
Remember: Metadata and file contents answer different questions.
3
Check SSH directory
Run test -d ~/.ssh.
Hint & worked example
Evaluate a file or string condition through its exit status rather than printed output.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
test -d ~/.ssh
```
Remember: A successful test usually prints nothing; inspect $? or chain a command.

Understand the pattern

Junior operators build confidence by gathering evidence before changing systems.

stat: Inspect a file or directory metadata record, including ownership, permissions, and size.
Metadata and file contents answer different questions.
test: Evaluate a file or string condition through its exit status rather than printed output.
A successful test usually prints nothing; inspect $? or chain a command.

Worked example and expected result

$ stat ~/.ssh/authorized_keys

Path: /home/learner/.ssh/authorized_keys
Type: file
Mode: -rw-------
Owner: learner
Group: learners
Size: 40 bytes

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

$ stat /srv/www/index.html

Path: /srv/www/index.html
Type: file
Mode: -rw-r--r--
Owner: www-data
Group: www-data
Size: 72 bytes

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

$ test -d ~/.ssh

(no output; exit 0)

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 permission audit”, which interpretation is safe?Metadata and file contents answer different questions.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 stat workflow from “Capstone permission audit” 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 network audit Try an incident drill

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