How do I learn using both the TUI and the Web GUI?

Clone https://github.com/1nc0gn30/30-days-of-Linux-Fundamentals and run ./control-panel for the native C terminal TUI (with built-in Markdown reader, Flashcard Arena, and /tmp sandbox shells), or use the Astro Web GUI for browser command drills, XP tracking, and visual chmod/FHS calculators.

Is 30 Days of Linux Fundamentals completely free?

Yes, 100% of the 30 days, 90 study guides, C TUI drills, and web tools are open-source and unlocked by default with zero paywalls.

← Back to 30-Day Curriculum

WEEK 5 · CAPSTONE SPRINT · TUI: ./control-panel --day 29

Day 29: Capstone Sprint I: Multi-Tier Linux Deployment

Deploy, network, and secure a production Linux service stack with automated systemd units and backups.

XP 0

Streak 0

Command Mastery 0%

Study Music

YouTube Study Radio

Pick a track or paste any YouTube URL.

🍳 Breakfast (Syntax) Session

Type commands, build streaks, and then review the source guide.

Live Terminal Drill

Re-type the command exactly to clear each challenge.

target$ loading...

0 / 12 mastered

Command Board

Tap a command when you practiced it in your own terminal.

Command Intel

Meaning

Command explanation will appear here.

Sample Output

Output preview will appear here.

Useful Fun Fact

Fun facts about the active command will appear here.

Last Run Output

Run a command to see result feedback.

Knowledge Boost

Faster learning with topic cues, mini-missions, and external docs.

Key Topics

⚡ 60-Second Mental Model (Student Digest)🍳 Day 29 Breakfast: System Hardening Techniques🌟 Objective🔌 Removing Unnecessary Services🛡️ Configuring Firewall Rules🔐 SSH Security Best Practices

Mini Missions

Mission 1: Run systemctl and explain the output in one sentence.
Mission 2: Run crontab and explain the output in one sentence.
Mission 3: Run journalctl and explain the output in one sentence.
Mission 4: Run mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29 and explain the output in one sentence.

Useful Resources

📖 Digestible Study Guide & Visual Architecture

Source: day-29-breakfast-study-guide.md · Synced with ./control-panel --day 29

Day 29 · Breakfast — Capstone Sprint I: Multi-Tier Linux Infrastructure Deployment

ZothOS × 1nc0gn30 Linux Dojo · Phase: Week 5 (Capstone Sprint) · Session: Breakfast (Morning Foundation & Core Command Syntax)

Core Commands: systemctl, nginx/caddy, ufw, rsync, crontab, journalctl

⚡ 60-Second Mental Model (Student Digest)

╔══════════════════════════════════════════════════════════════════════════════╗
║  ZOTHOS × 1NC0GN30 // SOVEREIGN LINUX OPERATOR CAPSTONE VERIFICATION         ║
╠══════════════════════════════════════════════════════════════════════════════╣
║                                                                              ║
║   1. PROVISION & MOUNT    ──►  lsblk • mkfs • /etc/fstab • chmod 750         ║
║   2. SERVICE ORCHESTRATION ──► systemctl enable --now • journalctl -u        ║
║   3. NETWORK & FIREWALL    ──► ss -tulpen • iptables / ufw • sshd_config     ║
║   4. AUDIT & BACKUP        ──► lynis audit • rsync -avz • sha256sum -c       ║
╚══════════════════════════════════════════════════════════════════════════════╝

Learning Pillar	How to Practice This Session
1. Native TUI (`./control-panel`)	Run `./control-panel` from repo root → Select Week 5 → Day 29 → Breakfast to drill interactive C lessons & quizzes.
2. Web Workstation (`astro-ui`)	Open `/day/29` → Select Breakfast tab → Type each target command in the live Mission Terminal to earn XP & streak mastery.
3. Safe Local Sandbox	Run `mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29` to test every flag below without touching production files.

🍳 Day 29 Breakfast: System Hardening Techniques

🌟 Objective

Learn essential hardening techniques to reduce system vulnerabilities and improve security posture.

🔌 Removing Unnecessary Services

Unneeded services can introduce vulnerabilities. Disable anything not in use:

systemctl list-unit-files --type=service
systemctl disable <service-name>

Examples to disable:

* cups (printing)
* avahi-daemon (zeroconf)
* bluetooth (if unused)

Tip: Use netstat -tulnp or ss -tuln to see what’s listening on ports.

🛡️ Configuring Firewall Rules

Use UFW or iptables to limit access:

# Allow SSH only from trusted IP
ufw allow from 192.168.1.10 to any port 22

# Deny all incoming by default
ufw default deny incoming

# Enable firewall
ufw enable

Best practices:

* Allow only required ports (e.g., 22, 80, 443)
* Deny by default, allow explicitly

🔐 SSH Security Best Practices

1. Disable root login:

nano /etc/ssh/sshd_config
# Change to:
PermitRootLogin no

2. Change default SSH port:

Port 2222

3. Use key-based auth only:

PasswordAuthentication no

4. Limit SSH users:

AllowUsers yourusername

Restart the SSH service after changes:

systemctl restart ssh

🧠 Review Questions

1. Why should unnecessary services be disabled?
2. What firewall command restricts SSH to a specific IP?
3. What setting disables SSH password login?
4. How can you verify which services are active?

📓 Recommended Reading

* UFW Essentials
* OpenSSH Hardening Guide
* System Hardening Guide by CIS

✅ Practice Task

* Disable an unused service on your system
* Configure UFW to allow only web and SSH traffic
* Apply at least 2 SSH hardening rules

Verify with:

sudo ufw status
sudo systemctl status ssh

🥪 Lunch (Workflows) Session

Type commands, build streaks, and then review the source guide.

Live Terminal Drill

Re-type the command exactly to clear each challenge.

target$ loading...

0 / 12 mastered

Command Board

Tap a command when you practiced it in your own terminal.

Command Intel

Meaning

Command explanation will appear here.

Sample Output

Output preview will appear here.

Useful Fun Fact

Fun facts about the active command will appear here.

Last Run Output

Run a command to see result feedback.

Knowledge Boost

Faster learning with topic cues, mini-missions, and external docs.

Key Topics

⚡ 60-Second Mental Model (Student Digest)🍽️ Day 29 Lunch: Security Audits and Tools🌟 Objective🔎 Using Lynis for System Audits🔍 Reviewing Logs for Suspicious Activity🚧 Patching and Updates

Mini Missions

Mission 1: Run systemctl and explain the output in one sentence.
Mission 2: Run crontab and explain the output in one sentence.
Mission 3: Run journalctl and explain the output in one sentence.
Mission 4: Run mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29 and explain the output in one sentence.

Useful Resources

📖 Digestible Study Guide & Visual Architecture

Source: day-29-lunch-study-guide.md · Synced with ./control-panel --day 29

Day 29 · Lunch — Capstone Sprint I: Multi-Tier Linux Infrastructure Deployment

ZothOS × 1nc0gn30 Linux Dojo · Phase: Week 5 (Capstone Sprint) · Session: Lunch (Midday Operational Workflows & Flag Mastery)

Core Commands: systemctl, nginx/caddy, ufw, rsync, crontab, journalctl

⚡ 60-Second Mental Model (Student Digest)

╔══════════════════════════════════════════════════════════════════════════════╗
║  ZOTHOS × 1NC0GN30 // SOVEREIGN LINUX OPERATOR CAPSTONE VERIFICATION         ║
╠══════════════════════════════════════════════════════════════════════════════╣
║                                                                              ║
║   1. PROVISION & MOUNT    ──►  lsblk • mkfs • /etc/fstab • chmod 750         ║
║   2. SERVICE ORCHESTRATION ──► systemctl enable --now • journalctl -u        ║
║   3. NETWORK & FIREWALL    ──► ss -tulpen • iptables / ufw • sshd_config     ║
║   4. AUDIT & BACKUP        ──► lynis audit • rsync -avz • sha256sum -c       ║
╚══════════════════════════════════════════════════════════════════════════════╝

Learning Pillar	How to Practice This Session
1. Native TUI (`./control-panel`)	Run `./control-panel` from repo root → Select Week 5 → Day 29 → Lunch to drill interactive C lessons & quizzes.
2. Web Workstation (`astro-ui`)	Open `/day/29` → Select Lunch tab → Type each target command in the live Mission Terminal to earn XP & streak mastery.
3. Safe Local Sandbox	Run `mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29` to test every flag below without touching production files.

🍽️ Day 29 Lunch: Security Audits and Tools

🌟 Objective

Learn how to audit your Linux system using industry-standard tools and practices, identify potential issues, and patch vulnerabilities effectively.

🔎 Using Lynis for System Audits

Lynis is a powerful auditing tool for Unix-based systems.

Install Lynis:

sudo apt update
sudo apt install lynis -y

Run an audit:

sudo lynis audit system

Check the report:

* Found at /var/log/lynis.log
* Suggestions and warnings help guide hardening efforts

🔍 Reviewing Logs for Suspicious Activity

Key logs to examine:

/var/log/auth.log      # Authentication logs
/var/log/syslog        # System messages
/var/log/kern.log      # Kernel events

Search for anomalies:

grep 'Failed password' /var/log/auth.log
grep 'error' /var/log/syslog

Use journalctl for persistent logs:

journalctl -xe

🚧 Patching and Updates

Keep your system secure with regular updates.

Debian/Ubuntu:

sudo apt update && sudo apt upgrade -y

RHEL/CentOS:

sudo yum update -y

List upgradable packages:

apt list --upgradable

Enable automatic updates:

sudo apt install unattended-upgrades
sudo dpkg-reconfigure --priority=low unattended-upgrades

🧠 Review Questions

1. What command installs Lynis?
2. Where can you find Lynis audit results?
3. Which log file shows SSH login attempts?
4. How can you automate security updates on Debian systems?

📓 Recommended Reading

* Lynis Documentation
* Linux Log File Reference
* Unattended Upgrades Guide

✅ Practice Task

* Install Lynis and run a system audit
* Review /var/log/auth.log for failed login attempts
* Enable automatic security updates

Confirm Lynis scan results:

sudo cat /var/log/lynis-report.dat | grep warning

🍽️ Dinner (Hardening) Session

Type commands, build streaks, and then review the source guide.

Live Terminal Drill

Re-type the command exactly to clear each challenge.

target$ loading...

0 / 12 mastered

Command Board

Tap a command when you practiced it in your own terminal.

Command Intel

Meaning

Command explanation will appear here.

Sample Output

Output preview will appear here.

Useful Fun Fact

Fun facts about the active command will appear here.

Last Run Output

Run a command to see result feedback.

Knowledge Boost

Faster learning with topic cues, mini-missions, and external docs.

Key Topics

⚡ 60-Second Mental Model (Student Digest)🍽️ Day 29 Dinner: Lab Session - Hardening Practice🌟 Objective🔧 Lab Task 1: Secure a Linux System🔎 Lab Task 2: Audit with Lynis🛡️ Lab Task 3: Finalize Firewall and SSH Settings

Mini Missions

Mission 1: Run systemctl and explain the output in one sentence.
Mission 2: Run crontab and explain the output in one sentence.
Mission 3: Run journalctl and explain the output in one sentence.
Mission 4: Run mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29 and explain the output in one sentence.

Useful Resources

📖 Digestible Study Guide & Visual Architecture

Source: day-29-dinner-study-guide.md · Synced with ./control-panel --day 29

Day 29 · Dinner — Capstone Sprint I: Multi-Tier Linux Infrastructure Deployment

ZothOS × 1nc0gn30 Linux Dojo · Phase: Week 5 (Capstone Sprint) · Session: Dinner (Evening Hardening, Pipelines & Verification Lab)

Core Commands: systemctl, nginx/caddy, ufw, rsync, crontab, journalctl

⚡ 60-Second Mental Model (Student Digest)

╔══════════════════════════════════════════════════════════════════════════════╗
║  ZOTHOS × 1NC0GN30 // SOVEREIGN LINUX OPERATOR CAPSTONE VERIFICATION         ║
╠══════════════════════════════════════════════════════════════════════════════╣
║                                                                              ║
║   1. PROVISION & MOUNT    ──►  lsblk • mkfs • /etc/fstab • chmod 750         ║
║   2. SERVICE ORCHESTRATION ──► systemctl enable --now • journalctl -u        ║
║   3. NETWORK & FIREWALL    ──► ss -tulpen • iptables / ufw • sshd_config     ║
║   4. AUDIT & BACKUP        ──► lynis audit • rsync -avz • sha256sum -c       ║
╚══════════════════════════════════════════════════════════════════════════════╝

Learning Pillar	How to Practice This Session
1. Native TUI (`./control-panel`)	Run `./control-panel` from repo root → Select Week 5 → Day 29 → Dinner to drill interactive C lessons & quizzes.
2. Web Workstation (`astro-ui`)	Open `/day/29` → Select Dinner tab → Type each target command in the live Mission Terminal to earn XP & streak mastery.
3. Safe Local Sandbox	Run `mkdir -p /tmp/linux-dojo-day-29 && cd /tmp/linux-dojo-day-29` to test every flag below without touching production files.

🍽️ Day 29 Dinner: Lab Session - Hardening Practice

🌟 Objective

Apply everything you've learned by actively hardening a Linux system using real-world tasks.

🔧 Lab Task 1: Secure a Linux System

#### ✅ Checklist:

* [ ] Disable unneeded services (cups, bluetooth, etc.)
* [ ] Remove unused user accounts
* [ ] Change default SSH port
* [ ] Disable root login via SSH
* [ ] Enforce strong password policies (/etc/login.defs)

Command Reference:

sudo systemctl disable cups
sudo userdel olduser
sudo nano /etc/ssh/sshd_config  # change port, disable root login

Restart SSH:

sudo systemctl restart ssh

🔎 Lab Task 2: Audit with Lynis

Run a full Lynis system audit:

sudo lynis audit system

Review the results:

* [ ] Review hardening_index
* [ ] Read suggestions at the bottom
* [ ] Address critical warnings

View report:

cat /var/log/lynis.log

Fix suggestions such as:

* Missing AppArmor/SELinux
* Insecure SSH settings
* Weak file permissions

🛡️ Lab Task 3: Finalize Firewall and SSH Settings

1. Firewall:

sudo ufw default deny incoming
sudo ufw allow 22
sudo ufw allow 80
sudo ufw enable

2. SSH Rules:

sudo nano /etc/ssh/sshd_config
# Set:
PermitRootLogin no
PasswordAuthentication no
AllowUsers youruser

Restart services:

sudo systemctl restart ssh
sudo ufw status

🧐 Review Questions

1. What does sudo lynis audit system do?
2. Where do you find Lynis recommendations?
3. How do you block all but specific ports with UFW?
4. What config file controls SSH settings?

📓 Additional Resources

* Lynis Documentation
* SSH Hardening Tips
* Ubuntu Hardening Guide

✅ Final Task

* Harden a VM or test box using the checklist
* Run lynis before and after to compare hardening index
* Export your final lynis.log for documentation