Run grep PermitRootLogin /etc/ssh/sshd_config.
grep PermitRootLogin /etc/ssh/sshd_config
Mission 245
SSH hardening deep review
Review SSH config, key mode, and host identity.
Security administrationgrepstatssh-keygen
Lesson 245 of 360
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Security administration · 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 stat ~/.ssh/authorized_keys.
stat ~/.ssh/authorized_keys
Run ssh-keygen -lf ~/.ssh/authorized_keys.
ssh-keygen -lf ~/.ssh/authorized_keys
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Lesson support
What to notice while you play.
Review SSH config, key mode, and host identity.
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.
stat <path>
Show lab file details.