grep Interview Questions and Answers¶

Introduction¶

These questions test whether you understand what grep does, when to use it, and how to verify the result on Linux.

Beginner Questions¶

What does grep do?

It searches text and prints matching lines.

Show a basic command.

grep root /etc/passwd

Intermediate Questions¶

Name useful options.

• -i: ignore case.
• -n: show line numbers.
• -R: search recursively.

Show a common administrator command.

grep -i error /var/log/messages

Scenario-Based Questions¶

How would you handle grep recursive search?

grep -R "PermitRootLogin" /etc/ssh

What would you verify afterward?

grep --version

Expected output should look similar to:

root:x:0:0:root:/root:/bin/bash

Practical Task Questions¶

Practice in a lab by running a safe version of the command, explaining the target, and showing the verification output.

Quick Review¶

grep root /etc/passwd
grep -i error /var/log/messages
grep --version

Related Guides¶

• What is grep?
• grep examples
• grep recursive search explained
• grep with Regex and Context

Summary¶

A strong grep answer includes the purpose, a correct example, a common mistake, and a verification command with output you can interpret.