Run printf rollback-reviewed | tee lab/rollback-note.txt.
printf rollback-reviewed | tee lab/rollback-note.txt
Lesson 189 of 360
0/360 lessons
0/17 missions
Troubleshooting · 8 minutes
New learnerrank
0XP
0%complete
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 cat lab/rollback-note.txt.
cat lab/rollback-note.txt
Run sha256sum lab/rollback-note.txt.
sha256sum lab/rollback-note.txt
Save progress
Keep learning across sessions.
Create a free account to sync completed lessons, XP, streaks, course status, and your next lesson across sessions.
Checking account status...
Progress sync is idle.
0XP
New learnerrank
0day streak
0best streak
0daily streak
0lessons
0courses
0missions
0tasks
Noverified
Progress sync stores completion IDs, scores, streaks, badges, and game settings. Terminal contents, editor snippets, lab scratch, email, and real names are never published on leaderboards or share cards.
Lesson support
What to notice while you play.
Write a rollback note from evidence.
Run the commands in order and compare the outputs.
Junior operators build confidence by gathering evidence before changing systems.
- Skipping the inspection step.
- Assuming one command tells the whole story.
Reference
Commands in this lesson.
printf <text>
Print formatted training text.
cat <file>
Print text file contents.
tee <file>
Write piped text to a lab file and keep it on screen.