Nginx

Nginx (pronounced "engine-x") is a high-performance web server, reverse proxy, and load balancer.

It is widely used for serving websites, handling API requests, and managing network traffic efficiently.

Features

Key Features of Nginx:

Web Server: Serves static and dynamic content with high concurrency.
Reverse Proxy: Forwards client requests to backend servers.
Load Balancer: Distributes traffic among multiple servers.
Caching: Improves performance by storing frequently accessed content.
Security: Can handle SSL termination and protect against DDoS attacks.

Configurations

Commands

Here’s a comprehensive list of Nginx commands for installation, configuration, management, and troubleshooting.

1️⃣ Install & Uninstall Nginx

Install Nginx

sudo apt update && sudo apt install nginx -y  # Ubuntu/Debian
sudo yum install nginx -y                     # CentOS/RHEL
sudo dnf install nginx -y                     # Fedora

Uninstall Nginx

sudo apt remove --purge nginx -y  # Ubuntu/Debian
sudo yum remove nginx -y          # CentOS/RHEL
sudo dnf remove nginx -y          # Fedora

2️⃣ Start, Stop, Restart, and Enable Nginx

Start Nginx

sudo systemctl start nginx

Stop Nginx

sudo systemctl stop nginx

Restart Nginx

sudo systemctl restart nginx

Reload Nginx (Apply config changes without downtime)

sudo systemctl reload nginx

Enable Nginx on boot

sudo systemctl enable nginx

Disable Nginx from starting on boot

sudo systemctl disable nginx

3️⃣ Check Nginx Status & Logs

Check if Nginx is running

sudo systemctl status nginx

Check Nginx version

nginx -v        # Short version
nginx -V        # Detailed version with compile options

Check Nginx configuration for errors

sudo nginx -t

Check Nginx logs

sudo tail -f /var/log/nginx/access.log  # Access logs
sudo tail -f /var/log/nginx/error.log   # Error logs

4️⃣ Manage Nginx Configuration

Nginx Main Config File

/etc/nginx/nginx.conf

Create a New Site Configuration

sudo nano /etc/nginx/sites-available/mywebsite.conf

Enable a Site (Create a symlink)

sudo ln -s /etc/nginx/sites-available/mywebsite.conf /etc/nginx/sites-enabled/

Disable a Site (Remove symlink)

sudo rm /etc/nginx/sites-enabled/mywebsite.conf

List Enabled Sites

ls /etc/nginx/sites-enabled/

5️⃣ Reload Nginx After Configuration Changes

sudo systemctl reload nginx

6️⃣ Manage Nginx Processes

Check running Nginx processes

ps aux | grep nginx

Kill Nginx process (Force stop)

sudo pkill nginx

sudo killall nginx

Restart all Nginx workers

sudo systemctl restart nginx

7️⃣ Firewall Rules for Nginx

Allow HTTP (Port 80) and HTTPS (Port 443)

sudo ufw allow 'Nginx Full'   # Ubuntu (UFW Firewall)
sudo firewall-cmd --add-service=http --permanent  # CentOS
sudo firewall-cmd --add-service=https --permanent
sudo firewall-cmd --reload

Check Allowed Services

sudo ufw status
sudo firewall-cmd --list-all

8️⃣ Test Nginx Configuration

Test syntax before reloading

sudo nginx -t

Simulate an HTTP request to check response

curl -I http://localhost
curl -I https://yourdomain.com

9️⃣ Enable Logging for Debugging

Increase error log level (Edit `nginx.conf`)

error_log  /var/log/nginx/error.log debug;

Then restart Nginx:

sudo systemctl restart nginx
sudo journalctl -u nginx

🔟 Useful Nginx Commands for Debugging

Check open ports (Make sure Nginx is listening)

sudo netstat -tulnp | grep nginx
sudo ss -tulnp | grep nginx

Check if a domain is resolving to your server

dig yourdomain.com +short
nslookup yourdomain.com

Check if Nginx is proxying correctly

curl -I -H "Host: yourdomain.com" http://localhost

Conclusion

🚀 These commands cover everything from installation to debugging in Nginx.

Would you like specific configurations for load balancing, caching, or SSL? 😃

Configuration by uses

Here are three separate Nginx configurations for each use case:

1. Web Server (Serving Static & Dynamic Content)

This configuration serves static files from /var/www/html and forwards PHP requests to a backend.

server {
    listen 80;
    server_name example.com;

    root /var/www/html;
    index index.html index.htm index.php;

    location / {
        try_files $uri $uri/ =404;
    }

    location ~ \.php$ {
        include fastcgi_params;
        fastcgi_pass unix:/run/php/php-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }
}

2. Reverse Proxy (Forwarding Requests to Backend Server)

This configuration forwards requests to a backend application running on port 5000.

proxy_pass 80/path to backend service, eg 127.0.0.1:8000

server {
    listen 80;
    server_name api.example.com;

    location / {
        proxy_pass http://127.0.0.1:5000;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

3. Load Balancer (Distributing Traffic Among Multiple Servers)

This setup distributes traffic among three backend servers.

Nginx uses Below Load balancing method

Round Robin (Default)

Requests are distributed sequentially across all available servers.
1st request to 1st server 2nd to 2nd S and 3rd to 3rd and 4rth request to 1 st server.

upstream backend_servers {
    server 192.168.1.101;
    server 192.168.1.102;
    server 192.168.1.103;
}

server {
    listen 80;
    server_name app.example.com;

    location / {
        proxy_pass http://backend_servers;  
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }
}

Let me know if you need any modifications! 🚀

Reverse Proxy

Use a Reverse Proxy if you want to protect backend servers, load balance, or improve security.
Use a Forward Proxy if you want to control outbound traffic, hide users (client)' identities, or bypass restrictions

Full Nginx Reverse Proxy Configuration File

Here’s a complete Nginx reverse proxy configuration file that: ✅ Routes requests to backend servers ✅ Handles SSL termination ✅ Supports WebSockets ✅ Adds security headers ✅ Caches static content

Step 1: Install Nginx

If you haven’t installed Nginx yet, install it using:

sudo apt update && sudo apt install nginx -y

Step 2: Create Reverse Proxy Configuration File

Create a new configuration file in /etc/nginx/sites-available/ (or /etc/nginx/conf.d/ in some setups):

sudo nano /etc/nginx/sites-available/reverse-proxy.conf

Paste the following configuration:

server {
    listen 80;
    server_name api.example.com;

    # Redirect all HTTP traffic to HTTPS
    return 301 https://$host$request_uri;
}

server {
    listen 443 ssl;
    server_name api.example.com;

    # SSL Certificates
    ssl_certificate /etc/nginx/ssl/fullchain.pem;
    ssl_certificate_key /etc/nginx/ssl/privkey.pem;

    # Security Headers
    add_header X-Frame-Options DENY;
    add_header X-Content-Type-Options nosniff;
    add_header X-XSS-Protection "1; mode=block";

    location / {
        proxy_pass http://backend_server:5000;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;

        # WebSocket Support
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "Upgrade";

        # Timeout settings
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;

        # Caching (for static content)
        location ~* \.(jpg|jpeg|png|gif|ico|css|js|woff|woff2|ttf|svg|mp4|webp|json)$ {
            expires 30d;
            add_header Cache-Control "public, no-transform";
        }
    }

    # Rate Limiting (optional)
    limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;
    location /api/ {
        limit_req zone=api_limit burst=20 nodelay;
        proxy_pass http://backend_server:5000;
    }
}

Step 3: Explanation of Configuration

1️⃣ HTTP to HTTPS Redirect

server {
    listen 80;
    server_name api.example.com;
    return 301 https://$host$request_uri;
}

✅ Redirects all HTTP traffic to HTTPS for security.

2️⃣ SSL Configuration (HTTPS)

server {
    listen 443 ssl;
    server_name api.example.com;

    ssl_certificate /etc/nginx/ssl/fullchain.pem;
    ssl_certificate_key /etc/nginx/ssl/privkey.pem;

✅ Configures SSL/TLS using certificates from Let’s Encrypt or another provider.

3️⃣ Reverse Proxy to Backend Server

location / {
    proxy_pass http://backend_server:5000;
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;

✅ Sends requests to backend server running on port 5000. ✅ Passes real client IP to the backend for logging.

4️⃣ WebSocket Support

proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "Upgrade";

✅ Supports WebSocket connections for real-time applications (e.g., chat, live updates).

5️⃣ Timeout Settings

proxy_connect_timeout 60s;
proxy_send_timeout 60s;
proxy_read_timeout 60s;

✅ Prevents long-running requests from being dropped.

6️⃣ Caching for Static Content

location ~* \.(jpg|jpeg|png|gif|ico|css|js|woff|woff2|ttf|svg|mp4|webp|json)$ {
    expires 30d;
    add_header Cache-Control "public, no-transform";
}

✅ Caches static files for 30 days to improve performance.

7️⃣ Rate Limiting (Optional)

limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;
location /api/ {
    limit_req zone=api_limit burst=20 nodelay;
    proxy_pass http://backend_server:5000;
}

✅ Limits API requests to 10 requests per second per user. ✅ Prevents abuse (DDoS attacks).

Step 4: Enable Configuration

Run the following commands to enable the reverse proxy:

sudo ln -s /etc/nginx/sites-available/reverse-proxy.conf /etc/nginx/sites-enabled/
sudo nginx -t  # Check for errors
sudo systemctl restart nginx  # Restart Nginx

Step 5: Test Reverse Proxy

Run the following command to test the reverse proxy:

curl -I https://api.example.com

✅ If everything is correct, you should receive a 200 OK response.

Conclusion

🚀 This configuration makes Nginx act as a powerful reverse proxy with: ✅ HTTPS & SSL termination ✅ WebSockets support ✅ Security headers ✅ Static content caching ✅ Rate limiting

Would you like a version with multiple backend servers (load balancing)? 🚀

PreviousDaily Responsibilities NextScenario based QA

Last updated 11 months ago

hashtagKey Features of Nginx:

hashtag1️⃣ Install & Uninstall Nginx

hashtagInstall Nginx

hashtagUninstall Nginx

hashtag2️⃣ Start, Stop, Restart, and Enable Nginx

hashtagStart Nginx

hashtagStop Nginx

hashtagRestart Nginx

hashtagReload Nginx (Apply config changes without downtime)

hashtagEnable Nginx on boot

hashtagDisable Nginx from starting on boot

hashtag3️⃣ Check Nginx Status & Logs

hashtagCheck if Nginx is running

hashtagCheck Nginx version

hashtagCheck Nginx configuration for errors

hashtagCheck Nginx logs

hashtag4️⃣ Manage Nginx Configuration

hashtagNginx Main Config File

hashtagCreate a New Site Configuration

hashtagEnable a Site (Create a symlink)

hashtagDisable a Site (Remove symlink)

hashtagList Enabled Sites

hashtag5️⃣ Reload Nginx After Configuration Changes

hashtag6️⃣ Manage Nginx Processes

hashtagCheck running Nginx processes

hashtagKill Nginx process (Force stop)

hashtagRestart all Nginx workers

hashtag7️⃣ Firewall Rules for Nginx

hashtagAllow HTTP (Port 80) and HTTPS (Port 443)

hashtagCheck Allowed Services

hashtag8️⃣ Test Nginx Configuration

hashtagTest syntax before reloading

hashtagSimulate an HTTP request to check response

hashtag9️⃣ Enable Logging for Debugging

hashtagIncrease error log level (Edit nginx.conf)

hashtag🔟 Useful Nginx Commands for Debugging

hashtagCheck open ports (Make sure Nginx is listening)

hashtagCheck if a domain is resolving to your server

hashtagCheck if Nginx is proxying correctly

hashtagConclusion

hashtag1. Web Server (Serving Static & Dynamic Content)

hashtag2. Reverse Proxy (Forwarding Requests to Backend Server)

hashtag3. Load Balancer (Distributing Traffic Among Multiple Servers)

hashtagRound Robin (Default)

hashtagFull Nginx Reverse Proxy Configuration File

hashtagStep 1: Install Nginx

hashtagStep 2: Create Reverse Proxy Configuration File

hashtagStep 3: Explanation of Configuration

hashtagStep 4: Enable Configuration

hashtagStep 5: Test Reverse Proxy

hashtagConclusion

Key Features of Nginx:

1️⃣ Install & Uninstall Nginx

Install Nginx

Uninstall Nginx

2️⃣ Start, Stop, Restart, and Enable Nginx

Start Nginx

Stop Nginx

Restart Nginx

Reload Nginx (Apply config changes without downtime)

Enable Nginx on boot

Disable Nginx from starting on boot

3️⃣ Check Nginx Status & Logs

Check if Nginx is running

Check Nginx version

Check Nginx configuration for errors

Check Nginx logs

4️⃣ Manage Nginx Configuration

Nginx Main Config File

Create a New Site Configuration

Enable a Site (Create a symlink)

Disable a Site (Remove symlink)

List Enabled Sites

5️⃣ Reload Nginx After Configuration Changes

6️⃣ Manage Nginx Processes

Check running Nginx processes

Kill Nginx process (Force stop)

Restart all Nginx workers

7️⃣ Firewall Rules for Nginx

Allow HTTP (Port 80) and HTTPS (Port 443)

Check Allowed Services

8️⃣ Test Nginx Configuration

Test syntax before reloading

Simulate an HTTP request to check response

9️⃣ Enable Logging for Debugging

Increase error log level (Edit `nginx.conf`)

🔟 Useful Nginx Commands for Debugging

Check open ports (Make sure Nginx is listening)

Check if a domain is resolving to your server

Check if Nginx is proxying correctly

Conclusion

1. Web Server (Serving Static & Dynamic Content)

2. Reverse Proxy (Forwarding Requests to Backend Server)

3. Load Balancer (Distributing Traffic Among Multiple Servers)

Round Robin (Default)

Full Nginx Reverse Proxy Configuration File

Step 1: Install Nginx

Step 2: Create Reverse Proxy Configuration File

Step 3: Explanation of Configuration

Step 4: Enable Configuration

Step 5: Test Reverse Proxy

Conclusion