Run cat README.txt.
cat README.txt
Mission 09
Viewing text
Open text, search logs, and inspect output without editing files.
Text and logscatheadtailgrepstat
Lesson 9 of 360
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Text and logs · 9 minutes
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learner@clairos:/home/learner $
Unix ops lab: type a command, press Enter
Instructions
9 minutes
Click any instruction for the command details, the why, and the common mistake to avoid.
Run tail -n 3 /var/log/auth.log.
tail -n 3 /var/log/auth.log
Run grep denied /var/log/auth.log.
grep denied /var/log/auth.log
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Lesson support
What to notice while you play.
Read file contents without changing them.
Use tail for logs and cat for small files.
Most troubleshooting starts by reading evidence.
- Opening huge logs with cat in a real terminal.
- Searching before checking which file you are reading.
Reference
Commands in this lesson.
cat <file>
Print text file contents.
head|tail [-n N] <file>
Read the beginning or end of a file.
grep [-i] <text> <file>
Find literal text inside a file.
stat <path>
Show lab file details.