Run nl /var/log/auth.log.
nl /var/log/auth.log
Mission 319
Numbered log reading
Add stable line numbers to a short authentication-log view.
Text and logsnlhead
Lesson 319 of 360
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Text and logs · 8 minutes
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learner@clairos:/home/learner $
Unix ops lab: type a command, press Enter
Instructions
8 minutes
Click any instruction for the command details, the why, and the common mistake to avoid.
Run nl /var/log/auth.log | head -n 3.
nl /var/log/auth.log | head -n 3
Run wc -l /var/log/auth.log.
wc -l /var/log/auth.log
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Lesson support
What to notice while you play.
Build repeatable confidence with citing exact lines from log evidence.
Start with nl /var/log/auth.log, inspect the result, then continue in order.
Citing exact lines from log evidence helps operators explain what they know before they change anything.
- Skipping the output that proves citing exact lines from log evidence.
- Changing several things before recording a baseline.
Reference
Commands in this lesson.
head|tail [-n N] <file>
Read the beginning or end of a file.
nl [file]
Number lines from a file or supported text pipeline.