Building a custom AMI allows you to bake your software and configurations into a template, enabling faster scaling and consistent deployments. The most common method is creating an image from an existing running or stopped EC2 instance.

Steps to Create an AMI

1
Launch an EC2 instance from a base AMI and configure it (install software, updates, etc.).
2
In the EC2 Console, select the instance and choose Actions > Image and templates > Create image.
3
Provide an image name and description.
4
Configure volume settings and choose whether to reboot the instance (reboot is recommended for data integrity).
5
Once the AMI status is 'available', you can use it to launch new identical instances.

AWS CLI Command to Create Image