Important
Without disabling the cloud-init network config, the netplan configuration will revert upon restarting your server. To disable the network configuration file, create a new network-config disabling configuration in `/etc/cloud/cloud.cfg.d/99-disable-network-config.cfg` with the following content:

network: {config: disabled}

1. Disable cloud-init networking:

Run the following command on each backend server to prevent configuration resets:

echo "network: {config: disabled}" > /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg

2. Update Netplan Configuration:

1. Find your Netplan configuration file (usually in /etc/netplan/).
2. Edit the file (e.g., sudo nano /etc/netplan/50-cloud-init.yaml).
3. Add your Load Balancer IP (Virtual IP) to the addresses list of your primary interface (e.g., eth0), with a /32 subnet.
   
   

Example Configuration:

network:
    ethernets:
        eth0:
            addresses:
            - 112.213.38.164/24       # Your Server's Primary IP
            - 103.17.56.158/32        # Your Load Balancer IP (Add this line)
            gateway4: 112.213.38.1
            match:
                macaddress: 00:16:3e:f8:fc:b5
            set-name: eth0
    version: 2

3. Apply Changes:

sudo netplan apply

Repeat these steps on all backend servers.

Step 2: Web Server Setup

Configure your web server software to respond to requests. Below are detailed instructions for both Apache and Nginx.

Method A: Apache

1. Install, Start, and Enable Apache:

sudo apt-get update
sudo apt-get install -y apache2
sudo systemctl start apache2
sudo systemctl enable apache2

2. Create a directory for your site:

sudo mkdir -p /var/www/html/test-site

3. Configure a VirtualHost:

Create a new configuration file:

sudo nano /etc/apache2/sites-available/test-site.conf

Add the following configuration (replace yourdomain.com with your actual domain or IP):

<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    ServerName yourdomain.com
    DocumentRoot /var/www/html/test-site
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>

4. Enable the Site and Reload:

sudo a2ensite test-site.conf
sudo systemctl reload apache2

Important
Without disabling the cloud-init network config, the netplan configuration will revert upon restarting your 
To support HTTPS (port 443), you must add a <VirtualHost *:443> block with SSLEngine on and paths to your certificates.

Method B: Nginx

1. Install, Start, and Enable Nginx:

sudo apt-get update
sudo apt-get install -y nginx
sudo systemctl start nginx
sudo systemctl enable nginx

2. Create a directory for your site:

sudo mkdir -p /var/www/html/test-site
# Create a test index file
echo "
Hello from Nginx
" | sudo tee /var/www/html/test-site/index.html

3. Configure a Server Block:

Create a new configuration file:

sudo nano /etc/nginx/sites-available/test-site

Add the following configuration:

server {
    listen 80;
    server_name yourdomain.com;

    root /var/www/html/test-site;
    index index.html;

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

4. Enable the Site and Reload:

sudo ln -s /etc/nginx/sites-available/test-site /etc/nginx/sites-enabled/
sudo nginx -t
sudo systemctl reload nginx

Health Checks & Troubleshooting

Common Issues:

• 503 Service Unavailable / Connection Timed Out:
  This almost always means the backend server is dropping the packet because it doesn't recognize the destination IP. Ensure you have completed Step 1 (adding the Load Balancer IP to the server's network interface).
• "No route to host" / Apt mirrors failing:
  If you see errors like Could not connect to mirror.binarylane.com.au:80 ... No route to host, review your netplan configuration. Ensure the CIDR for your Virtual IP (Load Balancer IP) is set to /32. If set incorrectly (e.g. /24), it may conflict with your gateway routes.
• Connection Refused:
  Ensure your web server (Apache/Nginx) is running and ports 80/443 are open in your firewall.

  sudo ufw allow 80/tcp
  sudo ufw allow 443/tcp

If you require assistance, feel free to submit a support ticket at our helpdesk here: Submit a ticket | BinaryLane