Azure VM Custom Data and User Data

• Custom Data and User Data are the scripts that can be executed while VM is being created (Provisioned)
• User Data is latest version of Custom Data where Azure Instance Metadata Service is accessible
• Steps

#!/bin/bash
apt update
apt install apache2 stress -y
apt install php libapache2-mod-php php-mysql -y
echo '<?php phpinfo(); ?>' > /var/www/html/info.php
systemctl restart apache2

• Lets create an Azure VM with the above as user data
  
  

Preparation

• Create a ubuntu linux vm
• Become a root user sudo -i
• Execute the following commands

apt update
apt install apache2 stress -y
apt install php libapache2-mod-php php-mysql -y
echo '<?php phpinfo(); ?>' > /var/www/html/info.php
systemctl restart apache2

• From the VM Created above, we can create resuable images.
• Azure Supports creating reusable images in two ways
  • Azure managed Image
  • Azure Compute Gallery

Generalized and Specialized VM Images

• Azure Generalized VM allows users to set credentials while provisioning, whereas specialized VM images don’t allow to set credentials
• Azure Managed Image:
  • This creates Generalized VM Images
• Azure Compute Gallery
  • This creates both Generalized as well as specialized VM Images
• Note: If we need to create Generalized VM Image, the user specific information has to be removed, so the source vm becomes unusable.

Create a Managed Image

• Click Capture
  
  
  
  
  
• Now lets try to create a vm with the captured image
  
  
  
• Note:
  • Learn JSON Refer Here