init

2026-01-29 14:26:02 +01:00
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--- a/README.md
+++ b/README.md
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+# Practice Exam - Setup Instructions
+
+## Overview
+
+This practice exam simulates a real-world server troubleshooting scenario with 5 problems to diagnose and fix within 45 minutes.
+
+## Requirements
+
+- Ubuntu Server (20.04 or 22.04 recommended)
+- Root/sudo access
+- Internet connection (for package installation)
+
+## Quick Start
+
+### 1. Initial Setup
+
+Run the setup script to install and configure all services:
+
+```bash
+sudo ./setup.sh
+```
+
+This will install and configure:
+- Nginx with 3 websites (company.local, shop.local, api.local)
+- PHP-FPM for the API
+- MySQL database with test data
+- Docker with a simple web application
+- UFW firewall
+
+### 2. Start the Exam
+
+Run the break server script and select option 6:
+
+```bash
+sudo ./break_server.sh
+```
+
+Select: `6) START EXAM (All 5 problems - 45 minutes)`
+
+### 3. Check Your Progress
+
+At any time, run the verification script:
+
+```bash
+./verify.sh
+```
+
+### 4. Reset (If Needed)
+
+To reset all problems and start over:
+
+```bash
+sudo ./break_server.sh
+# Select: 8) RESET all problems
+```
+
+## Files
+
+| File | Description |
+|------|-------------|
+| `setup.sh` | Initial server setup script |
+| `break_server.sh` | Interactive menu to break/reset services |
+| `verify.sh` | Check your progress on all tasks |
+| `tasks.md` | Exam task descriptions |
+| `solutions.md` | Detailed solutions (don't peek!) |
+
+## Tasks Overview
+
+1. **company.local** - Website not loading (Web Server Config)
+2. **shop.local** - 403 Forbidden error (File Permissions)
+3. **api.local:8080** - 502 Bad Gateway (Service Management)
+4. **localhost:8888** - Connection timeout (Firewall)
+5. **MySQL** - Connection refused (Database Admin)
+
+## Tips
+
+- Work systematically through each problem
+- Check service status first (`systemctl status`)
+- Read error logs (`journalctl`, `/var/log/`)
+- Test configurations before reloading (`nginx -t`)
+- Verify each fix before moving on
+
+Good luck!
--- a/break_server.sh
+++ b/break_server.sh
@@ -0,0 +1,455 @@
+#!/bin/bash
+
+# ============================================================
+# PRACTICE EXAM - BREAK SERVER SCRIPT
+# Betriebssysteme und Netzwerke - 45 Minute Practice Test
+# ============================================================
+# This script intentionally introduces problems for students
+# to diagnose and fix during the practice exam
+# ============================================================
+
+# Colors for output
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+BLUE='\033[0;34m'
+CYAN='\033[0;36m'
+MAGENTA='\033[0;35m'
+NC='\033[0m' # No Color
+
+print_status() {
+    echo -e "${BLUE}[*]${NC} $1"
+}
+
+print_success() {
+    echo -e "${GREEN}[✓]${NC} $1"
+}
+
+print_warning() {
+    echo -e "${YELLOW}[!]${NC} $1"
+}
+
+print_error() {
+    echo -e "${RED}[✗]${NC} $1"
+}
+
+print_break() {
+    echo -e "${MAGENTA}[BREAK]${NC} $1"
+}
+
+# Check if running as root
+if [[ $EUID -ne 0 ]]; then
+    print_error "This script must be run as root (use sudo)"
+    exit 1
+fi
+
+# Detect PHP version
+PHP_VERSION=$(php -r "echo PHP_MAJOR_VERSION.'.'.PHP_MINOR_VERSION;" 2>/dev/null || echo "8.3")
+
+# ============================================================
+# PROBLEM 1: Nginx Configuration Error (company.local)
+# Category: Web Server Configuration
+# ============================================================
+break_nginx_config() {
+    print_break "Breaking company.local (Nginx config error)..."
+
+    # Introduce a syntax error - remove semicolon
+    cat > /etc/nginx/sites-available/company.local << 'EOF'
+server {
+    listen 80;
+    server_name company.local;
+
+    root /var/www/company;
+    index index.html
+
+    location / {
+        try_files $uri $uri/ =404;
+    }
+
+    error_log /var/log/nginx/company_error.log;
+    access_log /var/log/nginx/company_access.log;
+}
+EOF
+
+    # Try to reload nginx (will fail silently)
+    nginx -t > /dev/null 2>&1 || true
+    systemctl reload nginx 2>/dev/null || systemctl restart nginx 2>/dev/null || true
+
+    print_success "Problem 1 active: company.local has a configuration error"
+}
+
+# ============================================================
+# PROBLEM 2: File Permissions (shop.local)
+# Category: File System Permissions
+# ============================================================
+break_file_permissions() {
+    print_break "Breaking shop.local (wrong file permissions)..."
+
+    # Remove all permissions from the website directory
+    chmod 000 /var/www/shop/index.html
+
+    print_success "Problem 2 active: shop.local has permission issues"
+}
+
+# ============================================================
+# PROBLEM 3: PHP-FPM Service Stopped (api.local)
+# Category: Service Management (systemd)
+# ============================================================
+break_php_service() {
+    print_break "Breaking api.local (PHP-FPM service stopped)..."
+
+    # Stop and disable PHP-FPM
+    systemctl stop php${PHP_VERSION}-fpm
+    systemctl disable php${PHP_VERSION}-fpm 2>/dev/null
+
+    print_success "Problem 3 active: API returns 502 Bad Gateway (PHP-FPM stopped)"
+}
+
+# ============================================================
+# PROBLEM 4: Firewall Blocking Docker App
+# Category: Firewall (UFW)
+# ============================================================
+break_firewall() {
+    print_break "Breaking Docker app access (firewall block)..."
+
+    # Block port 8888
+    ufw delete allow 8888/tcp > /dev/null 2>&1
+    ufw deny 8888/tcp > /dev/null 2>&1
+
+    print_success "Problem 4 active: Docker app unreachable (port blocked)"
+}
+
+# ============================================================
+# PROBLEM 5: MySQL User Configuration
+# Category: Database Administration
+# ============================================================
+break_mysql_user() {
+    print_break "Breaking MySQL database access..."
+
+    # Drop the working user and create one bound to wrong IP
+    mysql -e "DROP USER IF EXISTS 'webuser'@'localhost';"
+    mysql -e "CREATE USER 'webuser'@'10.0.0.1' IDENTIFIED BY 'WebPass123!';"
+    mysql -e "GRANT ALL PRIVILEGES ON practicedb.* TO 'webuser'@'10.0.0.1';"
+    mysql -e "FLUSH PRIVILEGES;"
+
+    print_success "Problem 5 active: MySQL connection refused (wrong host binding)"
+}
+
+# ============================================================
+# RESET FUNCTIONS
+# ============================================================
+reset_nginx_config() {
+    print_status "Resetting company.local configuration..."
+
+    cat > /etc/nginx/sites-available/company.local << 'EOF'
+server {
+    listen 80;
+    server_name company.local;
+
+    root /var/www/company;
+    index index.html;
+
+    location / {
+        try_files $uri $uri/ =404;
+    }
+
+    error_log /var/log/nginx/company_error.log;
+    access_log /var/log/nginx/company_access.log;
+}
+EOF
+
+    nginx -t > /dev/null 2>&1 && systemctl reload nginx
+    print_success "company.local restored"
+}
+
+reset_file_permissions() {
+    print_status "Resetting shop.local permissions..."
+
+    chmod 644 /var/www/shop/index.html
+    chown www-data:www-data /var/www/shop/index.html
+
+    print_success "shop.local permissions restored"
+}
+
+reset_php_service() {
+    print_status "Resetting PHP-FPM service..."
+
+    systemctl enable php${PHP_VERSION}-fpm
+    systemctl start php${PHP_VERSION}-fpm
+
+    print_success "PHP-FPM service restored"
+}
+
+reset_firewall() {
+    print_status "Resetting firewall rules..."
+
+    ufw delete deny 8888/tcp > /dev/null 2>&1
+    ufw allow 8888/tcp > /dev/null 2>&1
+
+    print_success "Firewall rules restored"
+}
+
+reset_mysql_user() {
+    print_status "Resetting MySQL user..."
+
+    mysql -e "DROP USER IF EXISTS 'webuser'@'10.0.0.1';"
+    mysql -e "DROP USER IF EXISTS 'webuser'@'localhost';"
+    mysql -e "CREATE USER 'webuser'@'localhost' IDENTIFIED BY 'WebPass123!';"
+    mysql -e "GRANT ALL PRIVILEGES ON practicedb.* TO 'webuser'@'localhost';"
+    mysql -e "FLUSH PRIVILEGES;"
+
+    print_success "MySQL user restored"
+}
+
+reset_all() {
+    echo ""
+    print_status "Resetting all problems..."
+    echo ""
+
+    reset_nginx_config
+    reset_file_permissions
+    reset_php_service
+    reset_firewall
+    reset_mysql_user
+
+    # Restart services
+    systemctl restart nginx
+
+    echo ""
+    print_success "All problems have been reset!"
+    echo ""
+}
+
+# ============================================================
+# START EXAM (ALL PROBLEMS)
+# ============================================================
+start_exam() {
+    echo ""
+    echo -e "${RED}============================================================${NC}"
+    echo -e "${RED}         STARTING PRACTICE EXAM - 45 MINUTES${NC}"
+    echo -e "${RED}============================================================${NC}"
+    echo ""
+
+    print_warning "Introducing 5 problems to the server..."
+    echo ""
+
+    break_nginx_config
+    break_file_permissions
+    break_php_service
+    break_firewall
+    break_mysql_user
+
+    # Restart nginx to apply changes
+    systemctl restart nginx 2>/dev/null || true
+
+    echo ""
+    echo -e "${RED}============================================================${NC}"
+    echo ""
+    print_warning "EXAM STARTED! You have 45 minutes to fix all issues."
+    echo ""
+    echo "The following services should be working when you're done:"
+    echo ""
+    echo "  Task 1: http://company.local        - Company Portal"
+    echo "  Task 2: http://shop.local           - Online Shop"
+    echo "  Task 3: http://api.local:8080       - REST API"
+    echo "  Task 4: http://localhost:8888       - Docker App"
+    echo "  Task 5: mysql -u webuser -p'WebPass123!' practicedb"
+    echo ""
+    echo "Use './verify.sh' to check your progress"
+    echo ""
+    echo -e "${RED}============================================================${NC}"
+    echo ""
+}
+
+# ============================================================
+# VERIFICATION
+# ============================================================
+verify_all() {
+    echo ""
+    echo "============================================================"
+    echo "             VERIFICATION RESULTS"
+    echo "============================================================"
+    echo ""
+
+    PASSED=0
+    FAILED=0
+
+    # Test company.local
+    echo -n "Task 1 - company.local:        "
+    if curl -s -o /dev/null -w "%{http_code}" http://company.local 2>/dev/null | grep -q "200"; then
+        echo -e "${GREEN}PASS${NC}"
+        ((PASSED++))
+    else
+        echo -e "${RED}FAIL${NC}"
+        ((FAILED++))
+    fi
+
+    # Test shop.local
+    echo -n "Task 2 - shop.local:           "
+    if curl -s http://shop.local 2>/dev/null | grep -q "Online Shop"; then
+        echo -e "${GREEN}PASS${NC}"
+        ((PASSED++))
+    else
+        echo -e "${RED}FAIL${NC}"
+        ((FAILED++))
+    fi
+
+    # Test API
+    echo -n "Task 3 - api.local:8080:       "
+    if curl -s http://api.local:8080 2>/dev/null | grep -q "success"; then
+        echo -e "${GREEN}PASS${NC}"
+        ((PASSED++))
+    else
+        echo -e "${RED}FAIL${NC}"
+        ((FAILED++))
+    fi
+
+    # Test Docker app
+    echo -n "Task 4 - Docker app :8888:     "
+    if curl -s http://localhost:8888 2>/dev/null | grep -q "Docker"; then
+        echo -e "${GREEN}PASS${NC}"
+        ((PASSED++))
+    else
+        echo -e "${RED}FAIL${NC}"
+        ((FAILED++))
+    fi
+
+    # Test MySQL
+    echo -n "Task 5 - MySQL connection:     "
+    if mysql -u webuser -p'WebPass123!' practicedb -e "SELECT 1;" > /dev/null 2>&1; then
+        echo -e "${GREEN}PASS${NC}"
+        ((PASSED++))
+    else
+        echo -e "${RED}FAIL${NC}"
+        ((FAILED++))
+    fi
+
+    echo ""
+    echo "============================================================"
+    echo ""
+    echo -e "Results: ${GREEN}${PASSED} PASSED${NC} | ${RED}${FAILED} FAILED${NC}"
+    echo ""
+
+    if [ $FAILED -eq 0 ]; then
+        echo -e "${GREEN}Congratulations! All tasks completed successfully!${NC}"
+    else
+        echo -e "${YELLOW}Keep working - ${FAILED} task(s) still need to be fixed.${NC}"
+    fi
+    echo ""
+    echo "============================================================"
+}
+
+# ============================================================
+# MAIN MENU
+# ============================================================
+show_menu() {
+    clear
+    echo ""
+    echo -e "${CYAN}============================================================${NC}"
+    echo -e "${CYAN}     PRACTICE EXAM - BREAK SERVER MENU${NC}"
+    echo -e "${CYAN}     Betriebssysteme und Netzwerke${NC}"
+    echo -e "${CYAN}============================================================${NC}"
+    echo ""
+    echo "  INDIVIDUAL PROBLEMS:"
+    echo ""
+    echo "    1) Break company.local    (Nginx config error)"
+    echo "    2) Break shop.local       (File permissions)"
+    echo "    3) Break api.local        (PHP-FPM service)"
+    echo "    4) Break Docker app       (Firewall block)"
+    echo "    5) Break MySQL            (User configuration)"
+    echo ""
+    echo "  EXAM MODE:"
+    echo ""
+    echo "    6) START EXAM (All 5 problems - 45 minutes)"
+    echo ""
+    echo "  UTILITIES:"
+    echo ""
+    echo "    7) Verify all services"
+    echo "    8) RESET all problems"
+    echo "    9) Reset specific problem"
+    echo ""
+    echo "    0) Exit"
+    echo ""
+    echo -e "${CYAN}============================================================${NC}"
+    echo ""
+}
+
+show_reset_menu() {
+    echo ""
+    echo "  SELECT PROBLEM TO RESET:"
+    echo ""
+    echo "    1) Reset company.local"
+    echo "    2) Reset shop.local"
+    echo "    3) Reset api.local (PHP-FPM)"
+    echo "    4) Reset Docker app (Firewall)"
+    echo "    5) Reset MySQL user"
+    echo "    6) Back to main menu"
+    echo ""
+}
+
+# ============================================================
+# MAIN LOOP
+# ============================================================
+while true; do
+    show_menu
+    read -p "  Select option: " choice
+
+    case $choice in
+        1)
+            break_nginx_config
+            systemctl restart nginx 2>/dev/null || true
+            read -p "Press Enter to continue..."
+            ;;
+        2)
+            break_file_permissions
+            read -p "Press Enter to continue..."
+            ;;
+        3)
+            break_php_service
+            read -p "Press Enter to continue..."
+            ;;
+        4)
+            break_firewall
+            read -p "Press Enter to continue..."
+            ;;
+        5)
+            break_mysql_user
+            read -p "Press Enter to continue..."
+            ;;
+        6)
+            start_exam
+            read -p "Press Enter to continue..."
+            ;;
+        7)
+            verify_all
+            read -p "Press Enter to continue..."
+            ;;
+        8)
+            reset_all
+            read -p "Press Enter to continue..."
+            ;;
+        9)
+            show_reset_menu
+            read -p "  Select problem to reset: " reset_choice
+            case $reset_choice in
+                1) reset_nginx_config ;;
+                2) reset_file_permissions ;;
+                3) reset_php_service ;;
+                4) reset_firewall ;;
+                5) reset_mysql_user ;;
+                6) continue ;;
+                *) print_error "Invalid option" ;;
+            esac
+            read -p "Press Enter to continue..."
+            ;;
+        0)
+            echo ""
+            print_status "Goodbye!"
+            exit 0
+            ;;
+        *)
+            print_error "Invalid option"
+            read -p "Press Enter to continue..."
+            ;;
+    esac
+done
--- a/setup.sh
+++ b/setup.sh
@@ -0,0 +1,442 @@
+#!/bin/bash
+
+# ============================================================
+# PRACTICE EXAM SETUP SCRIPT
+# Betriebssysteme und Netzwerke - 45 Minute Practice Test
+# ============================================================
+# This script sets up a server environment with multiple services
+# for students to practice system administration troubleshooting
+# ============================================================
+
+set -e
+
+# Colors for output
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+BLUE='\033[0;34m'
+NC='\033[0m' # No Color
+
+print_status() {
+    echo -e "${BLUE}[*]${NC} $1"
+}
+
+print_success() {
+    echo -e "${GREEN}[✓]${NC} $1"
+}
+
+print_warning() {
+    echo -e "${YELLOW}[!]${NC} $1"
+}
+
+print_error() {
+    echo -e "${RED}[✗]${NC} $1"
+}
+
+# Check if running as root
+if [[ $EUID -ne 0 ]]; then
+    print_error "This script must be run as root (use sudo)"
+    exit 1
+fi
+
+echo ""
+echo "============================================================"
+echo "     PRACTICE EXAM ENVIRONMENT SETUP"
+echo "     Betriebssysteme und Netzwerke"
+echo "============================================================"
+echo ""
+
+# ============================================================
+# STEP 1: Install required packages
+# ============================================================
+print_status "Updating package lists..."
+apt-get update -qq
+
+print_status "Installing required packages..."
+apt-get install -y -qq nginx mysql-server php-fpm php-mysql docker.io docker-compose ufw curl > /dev/null 2>&1
+print_success "Packages installed"
+
+# ============================================================
+# STEP 2: Configure Nginx - Website 1 (company.local)
+# ============================================================
+print_status "Setting up company.local website..."
+
+# Create website directory
+mkdir -p /var/www/company
+cat > /var/www/company/index.html << 'EOF'
+<!DOCTYPE html>
+<html lang="de">
+<head>
+    <meta charset="UTF-8">
+    <title>Company Portal</title>
+    <style>
+        body { font-family: Arial, sans-serif; margin: 40px; background: #f5f5f5; }
+        .container { background: white; padding: 30px; border-radius: 8px; max-width: 600px; margin: 0 auto; }
+        h1 { color: #2c3e50; }
+        .status { color: #27ae60; font-weight: bold; }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>Company Portal</h1>
+        <p class="status">Status: Online</p>
+        <p>Welcome to the internal company portal.</p>
+    </div>
+</body>
+</html>
+EOF
+
+# Set correct permissions
+chown -R www-data:www-data /var/www/company
+chmod -R 755 /var/www/company
+
+# Create Nginx config
+cat > /etc/nginx/sites-available/company.local << 'EOF'
+server {
+    listen 80;
+    server_name company.local;
+
+    root /var/www/company;
+    index index.html;
+
+    location / {
+        try_files $uri $uri/ =404;
+    }
+
+    error_log /var/log/nginx/company_error.log;
+    access_log /var/log/nginx/company_access.log;
+}
+EOF
+
+# Enable site
+ln -sf /etc/nginx/sites-available/company.local /etc/nginx/sites-enabled/
+print_success "company.local configured"
+
+# ============================================================
+# STEP 3: Configure Nginx - Website 2 (shop.local)
+# ============================================================
+print_status "Setting up shop.local website..."
+
+# Create website directory
+mkdir -p /var/www/shop
+cat > /var/www/shop/index.html << 'EOF'
+<!DOCTYPE html>
+<html lang="de">
+<head>
+    <meta charset="UTF-8">
+    <title>Online Shop</title>
+    <style>
+        body { font-family: Arial, sans-serif; margin: 40px; background: #e8f4f8; }
+        .container { background: white; padding: 30px; border-radius: 8px; max-width: 600px; margin: 0 auto; }
+        h1 { color: #3498db; }
+        .status { color: #27ae60; font-weight: bold; }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>Online Shop</h1>
+        <p class="status">Status: Online</p>
+        <p>Browse our products and enjoy shopping!</p>
+    </div>
+</body>
+</html>
+EOF
+
+# Set correct permissions
+chown -R www-data:www-data /var/www/shop
+chmod -R 755 /var/www/shop
+
+# Create Nginx config
+cat > /etc/nginx/sites-available/shop.local << 'EOF'
+server {
+    listen 80;
+    server_name shop.local www.shop.local;
+
+    root /var/www/shop;
+    index index.html;
+
+    location / {
+        try_files $uri $uri/ =404;
+    }
+
+    error_log /var/log/nginx/shop_error.log;
+    access_log /var/log/nginx/shop_access.log;
+}
+EOF
+
+# Enable site
+ln -sf /etc/nginx/sites-available/shop.local /etc/nginx/sites-enabled/
+print_success "shop.local configured"
+
+# ============================================================
+# STEP 4: Configure PHP-FPM API (api.local:8080)
+# ============================================================
+print_status "Setting up PHP API on api.local..."
+
+# Create API directory
+mkdir -p /var/www/api
+cat > /var/www/api/index.php << 'EOF'
+<?php
+header('Content-Type: application/json');
+
+$response = [
+    'status' => 'success',
+    'message' => 'API is running',
+    'timestamp' => date('Y-m-d H:i:s'),
+    'server' => 'Practice Exam Server',
+    'endpoints' => [
+        '/health' => 'Health check',
+        '/info' => 'Server information'
+    ]
+];
+
+echo json_encode($response, JSON_PRETTY_PRINT);
+?>
+EOF
+
+cat > /var/www/api/health.php << 'EOF'
+<?php
+header('Content-Type: application/json');
+echo json_encode(['status' => 'healthy', 'uptime' => shell_exec('uptime -p')]);
+?>
+EOF
+
+# Set permissions
+chown -R www-data:www-data /var/www/api
+chmod -R 755 /var/www/api
+
+# Detect PHP-FPM version
+PHP_VERSION=$(php -r "echo PHP_MAJOR_VERSION.'.'.PHP_MINOR_VERSION;")
+
+# Create API Nginx config
+cat > /etc/nginx/sites-available/api.local << EOF
+server {
+    listen 8080;
+    server_name api.local;
+
+    root /var/www/api;
+    index index.php;
+
+    location / {
+        try_files \$uri \$uri/ =404;
+    }
+
+    location ~ \.php\$ {
+        include snippets/fastcgi-php.conf;
+        fastcgi_pass unix:/var/run/php/php${PHP_VERSION}-fpm.sock;
+    }
+
+    error_log /var/log/nginx/api_error.log;
+    access_log /var/log/nginx/api_access.log;
+}
+EOF
+
+# Enable site
+ln -sf /etc/nginx/sites-available/api.local /etc/nginx/sites-enabled/
+print_success "api.local configured on port 8080"
+
+# ============================================================
+# STEP 5: Configure MySQL Database
+# ============================================================
+print_status "Setting up MySQL database..."
+
+# Start MySQL if not running
+systemctl start mysql
+systemctl enable mysql
+
+# Create database and user
+mysql -e "CREATE DATABASE IF NOT EXISTS practicedb;"
+mysql -e "CREATE USER IF NOT EXISTS 'webuser'@'localhost' IDENTIFIED BY 'WebPass123!';"
+mysql -e "GRANT ALL PRIVILEGES ON practicedb.* TO 'webuser'@'localhost';"
+mysql -e "FLUSH PRIVILEGES;"
+
+# Create test table with data
+mysql practicedb << 'EOF'
+CREATE TABLE IF NOT EXISTS products (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    name VARCHAR(100) NOT NULL,
+    price DECIMAL(10,2) NOT NULL,
+    stock INT DEFAULT 0,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+INSERT IGNORE INTO products (id, name, price, stock) VALUES
+(1, 'Laptop', 999.99, 50),
+(2, 'Mouse', 29.99, 200),
+(3, 'Keyboard', 79.99, 150),
+(4, 'Monitor', 299.99, 75);
+EOF
+
+print_success "MySQL database 'practicedb' configured"
+
+# ============================================================
+# STEP 6: Configure Docker Application
+# ============================================================
+print_status "Setting up Docker application..."
+
+# Start and enable Docker
+systemctl start docker
+systemctl enable docker
+
+# Create Docker app directory
+mkdir -p /opt/docker-app
+cat > /opt/docker-app/docker-compose.yml << 'EOF'
+version: '3'
+services:
+  webapp:
+    image: nginx:alpine
+    container_name: practice-webapp
+    ports:
+      - "8888:80"
+    volumes:
+      - ./html:/usr/share/nginx/html:ro
+    restart: unless-stopped
+EOF
+
+# Create simple HTML for Docker app
+mkdir -p /opt/docker-app/html
+cat > /opt/docker-app/html/index.html << 'EOF'
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Docker App</title>
+    <style>
+        body { font-family: Arial; background: #2c3e50; color: white; text-align: center; padding: 50px; }
+        .container { background: #34495e; padding: 30px; border-radius: 10px; display: inline-block; }
+        h1 { color: #1abc9c; }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <h1>Docker Application</h1>
+        <p>Running in a container on port 8888</p>
+    </div>
+</body>
+</html>
+EOF
+
+# Start Docker container
+cd /opt/docker-app
+docker-compose up -d
+print_success "Docker application started on port 8888"
+
+# ============================================================
+# STEP 7: Configure Firewall (UFW)
+# ============================================================
+print_status "Configuring firewall..."
+
+# Reset UFW to defaults
+ufw --force reset > /dev/null 2>&1
+
+# Set default policies
+ufw default deny incoming > /dev/null 2>&1
+ufw default allow outgoing > /dev/null 2>&1
+
+# Allow required ports
+ufw allow 22/tcp > /dev/null 2>&1    # SSH
+ufw allow 80/tcp > /dev/null 2>&1    # HTTP
+ufw allow 8080/tcp > /dev/null 2>&1  # API
+ufw allow 8888/tcp > /dev/null 2>&1  # Docker app
+ufw allow 3306/tcp > /dev/null 2>&1  # MySQL (local)
+
+# Enable firewall
+ufw --force enable > /dev/null 2>&1
+print_success "Firewall configured"
+
+# ============================================================
+# STEP 8: Configure /etc/hosts
+# ============================================================
+print_status "Configuring DNS entries in /etc/hosts..."
+
+# Remove old entries if they exist
+sed -i '/company\.local/d' /etc/hosts
+sed -i '/shop\.local/d' /etc/hosts
+sed -i '/api\.local/d' /etc/hosts
+
+# Add new entries
+echo "127.0.0.1 company.local" >> /etc/hosts
+echo "127.0.0.1 shop.local" >> /etc/hosts
+echo "127.0.0.1 www.shop.local" >> /etc/hosts
+echo "127.0.0.1 api.local" >> /etc/hosts
+
+print_success "/etc/hosts configured"
+
+# ============================================================
+# STEP 9: Start and enable services
+# ============================================================
+print_status "Starting all services..."
+
+# Enable and start PHP-FPM
+systemctl enable php${PHP_VERSION}-fpm
+systemctl start php${PHP_VERSION}-fpm
+
+# Test and reload Nginx
+nginx -t > /dev/null 2>&1
+systemctl enable nginx
+systemctl restart nginx
+
+print_success "All services started"
+
+# ============================================================
+# FINAL: Verification
+# ============================================================
+echo ""
+echo "============================================================"
+echo "                    SETUP COMPLETE"
+echo "============================================================"
+echo ""
+print_status "Verifying services..."
+echo ""
+
+# Test each service
+echo "Testing services:"
+echo ""
+
+# Test company.local
+if curl -s -o /dev/null -w "%{http_code}" http://company.local 2>/dev/null | grep -q "200"; then
+    print_success "company.local      → OK (HTTP 200)"
+else
+    print_error "company.local      → FAILED"
+fi
+
+# Test shop.local
+if curl -s -o /dev/null -w "%{http_code}" http://shop.local 2>/dev/null | grep -q "200"; then
+    print_success "shop.local         → OK (HTTP 200)"
+else
+    print_error "shop.local         → FAILED"
+fi
+
+# Test API
+if curl -s http://api.local:8080 2>/dev/null | grep -q "success"; then
+    print_success "api.local:8080     → OK (JSON response)"
+else
+    print_error "api.local:8080     → FAILED"
+fi
+
+# Test Docker app
+if curl -s -o /dev/null -w "%{http_code}" http://localhost:8888 2>/dev/null | grep -q "200"; then
+    print_success "Docker app :8888   → OK (HTTP 200)"
+else
+    print_error "Docker app :8888   → FAILED"
+fi
+
+# Test MySQL
+if mysql -u webuser -p'WebPass123!' practicedb -e "SELECT 1;" > /dev/null 2>&1; then
+    print_success "MySQL database     → OK (Connection successful)"
+else
+    print_error "MySQL database     → FAILED"
+fi
+
+echo ""
+echo "============================================================"
+echo "Server is ready for the practice exam!"
+echo ""
+echo "Available services:"
+echo "  - http://company.local        (Company Portal)"
+echo "  - http://shop.local           (Online Shop)"
+echo "  - http://api.local:8080       (REST API)"
+echo "  - http://localhost:8888       (Docker App)"
+echo "  - MySQL: webuser@localhost    (Database)"
+echo ""
+echo "Run 'sudo ./break_server.sh' to start the exam"
+echo "============================================================"
--- a/solutions.md
+++ b/solutions.md
@@ -0,0 +1,271 @@
+# Practice Exam Solutions
+
+## Task 1: Company Portal Unreachable
+
+### Diagnosis
+
+```bash
+# Check nginx status
+sudo systemctl status nginx
+
+# Test nginx configuration
+sudo nginx -t
+# Output: nginx: [emerg] unexpected "}" in /etc/nginx/sites-enabled/company.local:8
+
+# View the config file
+cat /etc/nginx/sites-available/company.local
+```
+
+### Problem
+The nginx configuration file for company.local has a **missing semicolon** after `index index.html`.
+
+### Solution
+
+```bash
+# Edit the configuration file
+sudo nano /etc/nginx/sites-available/company.local
+
+# Find this line:
+    index index.html
+
+# Change to (add semicolon):
+    index index.html;
+
+# Test configuration
+sudo nginx -t
+# Output: nginx: configuration file /etc/nginx/nginx.conf syntax is ok
+
+# Reload nginx
+sudo systemctl reload nginx
+```
+
+### Verification
+```bash
+curl http://company.local
+# Should return HTML with "Company Portal"
+```
+
+---
+
+## Task 2: Online Shop Shows 403 Forbidden
+
+### Diagnosis
+
+```bash
+# Check nginx error log
+sudo tail /var/log/nginx/shop_error.log
+# Output: open() "/var/www/shop/index.html" failed (13: Permission denied)
+
+# Check file permissions
+ls -la /var/www/shop/
+# Output: ---------- 1 www-data www-data ... index.html
+# (No permissions at all!)
+```
+
+### Problem
+The index.html file has **wrong permissions** (chmod 000 - no read/write/execute for anyone).
+
+### Solution
+
+```bash
+# Fix the file permissions
+sudo chmod 644 /var/www/shop/index.html
+
+# Verify permissions (should show -rw-r--r--)
+ls -la /var/www/shop/index.html
+```
+
+### Verification
+```bash
+curl http://shop.local
+# Should return HTML with "Online Shop"
+```
+
+---
+
+## Task 3: API Returns 502 Bad Gateway
+
+### Diagnosis
+
+```bash
+# Check nginx error log for API
+sudo tail /var/log/nginx/api_error.log
+# Output: connect() to unix:/var/run/php/php8.x-fpm.sock failed (2: No such file or directory)
+
+# Check PHP-FPM status
+sudo systemctl status php*-fpm
+# Output: Active: inactive (dead)
+```
+
+### Problem
+The **PHP-FPM service is stopped and disabled**. Nginx cannot forward PHP requests.
+
+### Solution
+
+```bash
+# Find the PHP-FPM version
+php -v
+# or: ls /etc/php/
+
+# Start PHP-FPM (replace 8.3 with your version if different)
+sudo systemctl start php8.3-fpm
+
+# Enable to start on boot
+sudo systemctl enable php8.3-fpm
+
+# Verify it's running
+sudo systemctl status php8.3-fpm
+# Should show: Active: active (running)
+```
+
+### Verification
+```bash
+curl http://api.local:8080
+# Should return JSON with "status": "success"
+```
+
+---
+
+## Task 4: Docker Application Unreachable
+
+### Diagnosis
+
+```bash
+# Check if Docker container is running
+sudo docker ps
+# Output: practice-webapp is running (HEALTHY)
+
+# Check if port is listening
+sudo ss -tulnp | grep 8888
+# Output: Shows docker-proxy listening on 8888
+
+# Check firewall status
+sudo ufw status
+# Output: 8888/tcp DENY Anywhere
+```
+
+### Problem
+The **firewall (UFW) is blocking port 8888**. The Docker container is running correctly, but connections are denied.
+
+### Solution
+
+```bash
+# Remove the deny rule
+sudo ufw delete deny 8888/tcp
+
+# Allow port 8888
+sudo ufw allow 8888/tcp
+
+# Verify firewall rules
+sudo ufw status
+# Should show: 8888/tcp ALLOW Anywhere
+```
+
+### Verification
+```bash
+curl http://localhost:8888
+# Should return HTML with "Docker Application"
+```
+
+---
+
+## Task 5: Database Connection Refused
+
+### Diagnosis
+
+```bash
+# Try to connect with the user
+mysql -u webuser -p'WebPass123!' practicedb
+# Output: ERROR 1045 (28000): Access denied for user 'webuser'@'localhost'
+
+# Check which users exist (as root)
+sudo mysql -e "SELECT user, host FROM mysql.user WHERE user='webuser';"
+# Output: webuser | 10.0.0.1
+# (User is bound to wrong IP, not localhost!)
+```
+
+### Problem
+The MySQL user `webuser` is bound to **wrong host IP** (10.0.0.1 instead of localhost).
+
+### Solution
+
+```bash
+# Connect as root
+sudo mysql
+
+# Create user for localhost (or recreate)
+DROP USER IF EXISTS 'webuser'@'10.0.0.1';
+CREATE USER 'webuser'@'localhost' IDENTIFIED BY 'WebPass123!';
+GRANT ALL PRIVILEGES ON practicedb.* TO 'webuser'@'localhost';
+FLUSH PRIVILEGES;
+EXIT;
+```
+
+Or as a one-liner:
+```bash
+sudo mysql -e "DROP USER IF EXISTS 'webuser'@'10.0.0.1'; CREATE USER 'webuser'@'localhost' IDENTIFIED BY 'WebPass123!'; GRANT ALL PRIVILEGES ON practicedb.* TO 'webuser'@'localhost'; FLUSH PRIVILEGES;"
+```
+
+### Verification
+```bash
+mysql -u webuser -p'WebPass123!' practicedb -e "SELECT * FROM products;"
+# Should show table with products (Laptop, Mouse, Keyboard, Monitor)
+```
+
+---
+
+## Quick Reference: Problem Summary
+
+| Task | Service | Problem | Key Fix |
+|------|---------|---------|---------|
+| 1 | company.local | Missing semicolon in nginx config | Add `;` after `index index.html` |
+| 2 | shop.local | Wrong file permissions (000) | `chmod 644 /var/www/shop/index.html` |
+| 3 | api.local | PHP-FPM service stopped | `systemctl start php*-fpm` |
+| 4 | localhost:8888 | Firewall blocking port | `ufw allow 8888/tcp` |
+| 5 | MySQL | User bound to wrong host | Create user for `'webuser'@'localhost'` |
+
+---
+
+## Diagnostic Approach
+
+For each problem, follow this systematic approach:
+
+1. **Check the symptom** - What error do you see?
+   - Connection refused → Service not running or firewall
+   - 403 Forbidden → Permissions issue
+   - 502 Bad Gateway → Backend service (PHP-FPM) down
+   - Connection timeout → Firewall blocking
+
+2. **Check service status** - Is the service running?
+   ```bash
+   systemctl status nginx
+   systemctl status php*-fpm
+   docker ps
+   ```
+
+3. **Check logs** - What do the logs say?
+   ```bash
+   journalctl -u nginx
+   tail /var/log/nginx/error.log
+   ```
+
+4. **Check configuration** - Is the config valid?
+   ```bash
+   nginx -t
+   cat /etc/nginx/sites-available/...
+   ```
+
+5. **Check permissions** - Can the service read the files?
+   ```bash
+   ls -la /var/www/...
+   ```
+
+6. **Check network** - Is the port accessible?
+   ```bash
+   ss -tulnp
+   ufw status
+   ```
+
+---
+
+*Practice Exam Solutions - Betriebssysteme und Netzwerke*
--- a/tasks.md
+++ b/tasks.md
@@ -0,0 +1,149 @@
+# Practice Exam - Betriebssysteme und Netzwerke
+
+## Exam Information
+
+- **Duration:** 45 minutes
+- **Tasks:** 5 problems to diagnose and fix
+- **Allowed:** 1x A4 cheat sheet (front and back)
+
+---
+
+## Scenario
+
+You are a system administrator for a company. Multiple services on the server have stopped working after a colleague made some changes. Your task is to diagnose and fix all issues.
+
+---
+
+## Task 1: Company Portal Unreachable
+
+**Service:** http://company.local
+
+**Problem:** The company portal website is not loading. Users report seeing an error page or the page won't load at all.
+
+**Expected Result:** The website should display "Company Portal" with "Status: Online"
+
+**Test Command:**
+```bash
+curl http://company.local
+```
+
+**Category:** Web Server Configuration
+
+---
+
+## Task 2: Online Shop Shows 403 Forbidden
+
+**Service:** http://shop.local
+
+**Problem:** The online shop returns a "403 Forbidden" error when accessed.
+
+**Expected Result:** The website should display "Online Shop" with "Status: Online"
+
+**Test Command:**
+```bash
+curl http://shop.local
+```
+
+**Category:** File System Permissions
+
+---
+
+## Task 3: API Returns 502 Bad Gateway
+
+**Service:** http://api.local:8080
+
+**Problem:** The REST API returns a "502 Bad Gateway" error instead of JSON data.
+
+**Expected Result:** The API should return a JSON response with `"status": "success"`
+
+**Test Command:**
+```bash
+curl http://api.local:8080
+```
+
+**Category:** Service Management (systemd)
+
+---
+
+## Task 4: Docker Application Unreachable
+
+**Service:** http://localhost:8888
+
+**Problem:** The Docker web application running on port 8888 is not accessible. The connection times out.
+
+**Expected Result:** The page should display "Docker Application" running in a container.
+
+**Test Command:**
+```bash
+curl http://localhost:8888
+```
+
+**Hint:** The Docker container itself is running correctly.
+
+**Category:** Firewall (UFW)
+
+---
+
+## Task 5: Database Connection Refused
+
+**Service:** MySQL Database
+
+**Problem:** The web application cannot connect to the MySQL database. Connection attempts with the `webuser` account are being refused.
+
+**Credentials:**
+- Username: `webuser`
+- Password: `WebPass123!`
+- Database: `practicedb`
+
+**Expected Result:** Should be able to connect and query the database.
+
+**Test Command:**
+```bash
+mysql -u webuser -p'WebPass123!' practicedb -e "SELECT * FROM products;"
+```
+
+**Category:** Database Administration
+
+---
+
+## Verification
+
+Run the verification script to check your progress:
+
+```bash
+sudo ./break_server.sh
+# Then select option 7) Verify all services
+```
+
+Or test each service manually with the curl commands above.
+
+---
+
+## Diagnostic Commands Reference
+
+| Tool | Purpose |
+|------|---------|
+| `systemctl status <service>` | Check service status |
+| `systemctl start/restart <service>` | Start or restart service |
+| `nginx -t` | Test nginx configuration |
+| `journalctl -u <service>` | View service logs |
+| `ufw status` | Check firewall rules |
+| `ss -tulnp` | Show listening ports |
+| `ls -la <path>` | Check file permissions |
+| `docker ps` | List running containers |
+| `cat /var/log/nginx/error.log` | View nginx error logs |
+
+---
+
+## Good Luck!
+
+Remember to work systematically:
+1. Identify the symptom
+2. Check service status
+3. Review configuration/logs
+4. Apply the fix
+5. Verify the solution
+
+---
+
+*Practice Exam - Betriebssysteme und Netzwerke*
--- a/verify.sh
+++ b/verify.sh
@@ -0,0 +1,90 @@
+#!/bin/bash
+
+# ============================================================
+# PRACTICE EXAM - VERIFICATION SCRIPT
+# Run this to check your progress
+# ============================================================
+
+# Colors
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m'
+
+echo ""
+echo "============================================================"
+echo "           PRACTICE EXAM - VERIFICATION"
+echo "============================================================"
+echo ""
+
+PASSED=0
+FAILED=0
+
+# Task 1: company.local
+echo -n "Task 1 - company.local (Nginx Config):    "
+if curl -s http://company.local 2>/dev/null | grep -q "Company Portal"; then
+    echo -e "${GREEN}PASS${NC}"
+    ((PASSED++))
+else
+    echo -e "${RED}FAIL${NC}"
+    ((FAILED++))
+fi
+
+# Task 2: shop.local
+echo -n "Task 2 - shop.local (Permissions):        "
+if curl -s http://shop.local 2>/dev/null | grep -q "Online Shop"; then
+    echo -e "${GREEN}PASS${NC}"
+    ((PASSED++))
+else
+    echo -e "${RED}FAIL${NC}"
+    ((FAILED++))
+fi
+
+# Task 3: api.local
+echo -n "Task 3 - api.local:8080 (PHP-FPM):        "
+if curl -s http://api.local:8080 2>/dev/null | grep -q "success"; then
+    echo -e "${GREEN}PASS${NC}"
+    ((PASSED++))
+else
+    echo -e "${RED}FAIL${NC}"
+    ((FAILED++))
+fi
+
+# Task 4: Docker app
+echo -n "Task 4 - Docker App :8888 (Firewall):     "
+if curl -s --connect-timeout 3 http://localhost:8888 2>/dev/null | grep -q "Docker"; then
+    echo -e "${GREEN}PASS${NC}"
+    ((PASSED++))
+else
+    echo -e "${RED}FAIL${NC}"
+    ((FAILED++))
+fi
+
+# Task 5: MySQL
+echo -n "Task 5 - MySQL Database (User):           "
+if mysql -u webuser -p'WebPass123!' practicedb -e "SELECT 1;" > /dev/null 2>&1; then
+    echo -e "${GREEN}PASS${NC}"
+    ((PASSED++))
+else
+    echo -e "${RED}FAIL${NC}"
+    ((FAILED++))
+fi
+
+echo ""
+echo "============================================================"
+echo ""
+echo -e "Score: ${GREEN}${PASSED}/5 PASSED${NC} | ${RED}${FAILED}/5 FAILED${NC}"
+echo ""
+
+if [ $FAILED -eq 0 ]; then
+    echo -e "${GREEN}============================================${NC}"
+    echo -e "${GREEN}  CONGRATULATIONS! All tasks completed!    ${NC}"
+    echo -e "${GREEN}============================================${NC}"
+elif [ $PASSED -ge 3 ]; then
+    echo -e "${YELLOW}Good progress! Keep going - ${FAILED} task(s) remaining.${NC}"
+else
+    echo -e "${YELLOW}${FAILED} task(s) still need to be fixed.${NC}"
+fi
+
+echo ""
+echo "============================================================"