Installing NGINX, LetsEncrypt and Docker

To install Let's Encrypt with Nginx and proxy traffic to an application running on port 3000, you will use the following tools:

1. **Nginx**: To handle the proxying.

2. **Certbot**: To install and manage SSL certificates from Let's Encrypt.

Here is a step-by-step guide to set up Let's Encrypt on Nginx and proxy traffic to an application running on port 3000.

---

### **Step 1: Install Nginx**

If Nginx is not already installed, you can install it using the following command:

1sudo apt update
2sudo apt install nginx

### **Step 2: Install Certbot for Let's Encrypt**

Certbot is the tool that helps you automatically issue and renew SSL certificates from Let's Encrypt.

1. **Install Certbot** and the Nginx plugin:

1   sudo apt install certbot python3-certbot-nginx

2. **Verify the Certbot installation**:

1certbot --version

You should see the version of Certbot installed.

---

### **Step 3: Configure Nginx as a Reverse Proxy**

You'll need to configure Nginx to act as a reverse proxy, sending traffic from port 80/443 (HTTP/HTTPS) to your application running on port 3000.

1. **Create a new Nginx server block (virtual host)** for your domain. The configuration files are typically located in `/etc/nginx/sites-available/`.

1sudo nano /etc/nginx/sites-available/your-domain.com

2. **Add the following configuration to proxy requests to port 3000**:

1server {
2       listen 80;
3       server_name your-domain.com www.your-domain.com;
4
5       location / {
6           proxy_pass http://localhost:3000;
7           proxy_set_header Host $host;
8           proxy_set_header X-Real-IP $remote_addr;
9           proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
10           proxy_set_header X-Forwarded-Proto $scheme;
11       }
12   }

- **`server_name`**: Replace `your-domain.com` with your actual domain name.

- **`proxy_pass`**: Specifies that incoming traffic should be proxied to your application running on port 3000.

- **`proxy_set_header`**: Ensures the correct headers are forwarded to the backend application.

3. **Enable the Nginx configuration** by creating a symbolic link to it in the `sites-enabled` directory:

1sudo ln -s /etc/nginx/sites-available/your-domain.com /etc/nginx/sites-enabled/

4. **Test the Nginx configuration** to make sure there are no syntax errors:

1sudo nginx -t

5. **Reload Nginx** to apply the changes:

1   sudo systemctl reload nginx

---

### **Step 4: Obtain SSL Certificates from Let's Encrypt**

Now that Nginx is set up to proxy traffic to your app, let's use Certbot to obtain SSL certificates.

1. **Run Certbot** to obtain and install an SSL certificate for your domain:

1   sudo certbot --nginx -d your-domain.com -d www.your-domain.com

Certbot will automatically:

- Obtain the SSL certificate from Let's Encrypt.

- Modify your Nginx configuration to redirect HTTP to HTTPS.

- Apply the SSL certificate to your Nginx configuration.

2. **Follow the prompts**:

- Certbot will ask you to provide an email address for important renewal or security notices.

- It will also ask if you want to automatically redirect all HTTP traffic to HTTPS (this is recommended).

---

### **Step 5: Test the HTTPS Configuration**

1. **Test the SSL setup**:

- Open your web browser and navigate to `https://your-domain.com`. You should see that your site is served over HTTPS and is correctly proxied to the application running on port 3000.

2. **Verify the certificate renewal**:

- Certbot automatically renews the SSL certificates. You can verify the renewal configuration by running:

1sudo certbot renew --dry-run

---

### **Nginx Configuration After Certbot Runs**

After Certbot automatically configures SSL, your Nginx configuration will look like this:

1server {
2    listen 80;
3    server_name your-domain.com www.your-domain.com;
4    return 301 https://$host$request_uri;
5}
6
7server {
8    listen 443 ssl;
9    server_name your-domain.com www.your-domain.com;
10
11    ssl_certificate /etc/letsencrypt/live/your-domain.com/fullchain.pem;
12    ssl_certificate_key /etc/letsencrypt/live/your-domain.com/privkey.pem;
13    include /etc/letsencrypt/options-ssl-nginx.conf;
14    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
15
16    location / {
17        proxy_pass http://localhost:3000;
18        proxy_set_header Host $host;
19        proxy_set_header X-Real-IP $remote_addr;
20        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
21        proxy_set_header X-Forwarded-Proto $scheme;
22    }
23}

- This configuration redirects all HTTP traffic to HTTPS.

- It serves the SSL certificate from the `/etc/letsencrypt/` directory.

- The traffic is proxied to your application running on port `3000`.

---

### **Summary of Steps**

1. **Install Nginx** and **Certbot**.

2. **Configure Nginx** to act as a reverse proxy for your application on port 3000.

3. **Use Certbot** to obtain and install SSL certificates from Let's Encrypt.

4. **Test HTTPS** to ensure everything is working correctly.

With these steps, you’ll have a secure connection with HTTPS using Let's Encrypt, and Nginx will proxy the requests to your application running on port 3000.