Practice Use drills for recall and labs for real operating judgment.

LAB-FS-02 - Inside /etc - The Config Vault

Inspect common files inside /etc in read-only mode so you can recognize system configuration safely and confidently.

FS File System Mastery

Inside /etc - The Config Vault

Inspect common files inside /etc in read-only mode so you can recognize system configuration safely and confidently.

40 min BEGINNER LINUX Field-verified
Prerequisites
Lab LAB-FS-01 - The Linux File System Tree
Success criteria
  • Read a few important files in /etc and describe what each one controls.
  • Recognize that many system settings are plain text.
Safety notes
  • Stay in read-only mode for this lab. Do not edit live files in /etc while learning.

Part A: The Field Guide

/etc is where Linux keeps many system-wide configuration files.

For beginners, the most important insight is simple: these are usually plain text files that you can inspect with normal reading tools. That makes Linux more transparent, but it also means careless edits can break real behavior.

First Rule of /etc

Read first. Edit later. If a file says it is auto-generated or managed by another tool, respect that warning.

Good starter files

  • /etc/os-release: identifies the Linux distribution
  • /etc/hosts: local hostname mappings
  • /etc/passwd: account records, not passwords
  • /etc/resolv.conf: DNS settings or pointers to DNS management

Part B: The Drill Deck

Terminal required: this lab is about reading and interpreting, not changing settings.

G
Guided Step by step - type exactly this and compare the result
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Exercise G1: Identify the machine

  1. Run cat /etc/os-release
  2. Find PRETTY_NAME
  3. Say which Linux distribution you are on

Exercise G2: Inspect local name resolution

  1. Run cat /etc/hosts
  2. Find the line that mentions localhost
  3. Notice that comments begin with #

Exercise G3: Read the account list

  1. Run cat /etc/passwd
  2. Notice that each line describes one account
  3. If column is available, make it easier to read: cat /etc/passwd | column -s: -t
S
Solo Task described, hints available - figure it out
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Exercise S1: Check DNS configuration

  1. Run cat /etc/resolv.conf
  2. Look for nameserver lines
  3. If the file says not to edit it by hand, note that and leave it alone

Exercise S2: Explore .d directories

  1. Run cd /etc
  2. Run ls -ld *.d
  3. Pick one directory and list its contents
  4. Notice how Linux often uses small drop-in config files instead of one huge file
M
Mission Real scenario - no hints, combine multiple skills
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Mission M1: Practice a safe backup habit

Do not write inside /etc for this mission. Instead:

  1. Create a practice folder in your home directory: mkdir -p ~/etc-practice
  2. Copy a safe file for inspection: cp /etc/hosts ~/etc-practice/hosts.backup
  3. Verify it exists: ls -l ~/etc-practice
  4. Read the copied file from your home directory

That teaches the right habit: make a backup or working copy before experimenting.