Files and paths · Lesson 14 of 36 · 7 minutes

SSH file layout

Inspect common SSH files without making any network connection.

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

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1
List SSH folder
Run ls -la ~/.ssh.
Hint & worked example
List directory entries; -a includes hidden names and -l adds ownership and permission detail.
The command outcome must match the task, including successful access or the explicitly requested failure.
```
ls -la ~/.ssh
```
Remember: A listing is not proof that you can read or modify every listed file.
2
Read SSH config
Run cat ~/.ssh/config.
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 ~/.ssh/config
```
Remember: Reading a source file should precede changing it; avoid printing real secrets.
3
Inspect authorized keys
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.

Understand the pattern

SSH file layout matters for secure admin access.

ls: List directory entries; -a includes hidden names and -l adds ownership and permission detail.
A listing is not proof that you can read or modify every listed file.
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.
stat: Inspect a file or directory metadata record, including ownership, permissions, and size.
Metadata and file contents answer different questions.

Worked example and expected result

$ ls -la ~/.ssh

--rw------- learner learners    40 authorized_keys
--rw------- learner learners    87 config
--rw------- learner learners    84 known_hosts

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

$ cat ~/.ssh/config

Host lab
  HostName clairos-learn-lab
  User learner
  IdentityFile ~/.ssh/training_key

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

$ 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.

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 “SSH file layout”, which interpretation is safe?A command appearing in history proves it completed successfully.A successful first check guarantees that every dependent service is healthy.Reading a source file should precede changing it; avoid printing real secrets.

Apply it elsewhere

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

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Scratch workspace Try an incident drill

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