Continue your lesson
Connect the command you run to the file, process, service, permission, or kernel state it changes.
Block 1 of 3Compare SSH hardening · SELinux
Current · 11 min
Compare SSH hardening · SELinux
Optional concept notes
SSH hardening
Reduces remote attack surface through stricter daemon configuration.
SELinux
Enforces mandatory access rules using labels and policy.
Complete one provider lesson, then answer four related questions. That is enough for today; more practice is optional.
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Block 2 of 3Understand sudo
12 min
Understand sudo
Optional concept notes
sudo
Delegates selected privileged commands according to explicit policy.
Complete one provider lesson, then answer four related questions. That is enough for today; more practice is optional.
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Block 3 of 3Understand noexec mount option
8 min
Understand noexec mount option
Optional concept notes
noexec mount option
Prevents direct execution of binaries from a mounted filesystem.
Complete one provider lesson, then answer four related questions. That is enough for today; more practice is optional.
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Practice the reasoning here
Use a disposable Linux system. Predict a command's effect, run it, inspect exit status and logs, then restore the starting state.
- State the expected result before changing or testing anything.
- Name the observation, command, log, or report that would confirm it.
- Explain why the closest alternative does not fit the same requirement.
Check the whole objective
This unlocks objective 3.3 for recall. The latest checkpoint needs 70% or higher; a lower result puts the lesson back near the front of your timeline.