Run sed s/443/8443/ data/config-a.conf.
sed s/443/8443/ data/config-a.conf
Mission 323
Config substitution preview
Preview a port substitution and compare it with the unchanged source.
Text and logssedgrepnl
Lesson 323 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 grep listen data/config-a.conf.
grep listen data/config-a.conf
Run nl data/config-a.conf.
nl data/config-a.conf
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Lesson support
What to notice while you play.
Build repeatable confidence with previewing a text change before editing a config.
Start with sed s/443/8443/ data/config-a.conf, inspect the result, then continue in order.
Previewing a text change before editing a config helps operators explain what they know before they change anything.
- Skipping the output that proves previewing a text change before editing a config.
- Changing several things before recording a baseline.
Reference
Commands in this lesson.
grep [-i] <text> <file>
Find literal text inside a file.
sed s/old/new/ <file>
Preview simple text substitutions.
nl [file]
Number lines from a file or supported text pipeline.