Permissions and users · Lesson 10 of 33 · 6 minutes

Protected paths

Try a blocked system delete and inspect the protected file.

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
Try blocked delete
Run rm /etc/passwd.
Hint & worked example
Remove the named file from the virtual workspace. The training root and system trees are guarded.
Observe the simulator safety refusal; no protected target is removed.
```
rm /etc/passwd
```
Remember: Simulator protections are not a promise that a real shell will protect the same target.
2
Inspect passwd
Run stat /etc/passwd.
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 /etc/passwd
```
Remember: Metadata and file contents answer different questions.
3
Confirm user
Run whoami.
Hint & worked example
Print the effective user name.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
whoami
```
Remember: An elevated command can run with a different effective identity from the normal shell.

Understand the pattern

Safety controls matter when teaching destructive commands.

rm: Remove the named file from the virtual workspace. The training root and system trees are guarded.
Simulator protections are not a promise that a real shell will protect the same target.
stat: Inspect a file or directory metadata record, including ownership, permissions, and size.
Metadata and file contents answer different questions.
whoami: Print the effective user name.
An elevated command can run with a different effective identity from the normal shell.

Worked example and expected result

$ rm /etc/passwd

System paths are protected. Remove files only inside /home/learner.

Exit status: 1. This nonzero result is an expected part of this exercise.

$ stat /etc/passwd

Path: /etc/passwd
Type: file
Mode: -rw-r--r--
Owner: root
Group: root
Size: 147 bytes

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

$ whoami

learner

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 “Protected paths”, which interpretation is safe?A successful first check guarantees that every dependent service is healthy.Metadata and file contents answer different questions.A command appearing in history proves it completed successfully.

Apply it elsewhere

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

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Group collaboration Try an incident drill

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