Run grep warn /var/log/nginx-error.log | tee lab/rollback-evidence.txt.
grep warn /var/log/nginx-error.log | tee lab/rollback-evidence.txt
Mission 292
Incident rollback evidence
Capture rollback evidence before writing a note.
Troubleshootinggrepteesha256sum
Lesson 292 of 360
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Troubleshooting · 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 sha256sum lab/rollback-evidence.txt.
sha256sum lab/rollback-evidence.txt
Run cat data/incident-template.md.
cat data/incident-template.md
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Lesson support
What to notice while you play.
Capture rollback evidence before writing a note.
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.
grep [-i] <text> <file>
Find literal text inside a file.
tee <file>
Write piped text to a lab file and keep it on screen.
sha256sum <file>
Print a deterministic training checksum.