AWS Certified Cloud Practitioner / EC2 Instance Storage

AMI Overview

🧩 What is an AMI (Amazon Machine Image)?

An AMI is a pre-configured template for launching EC2 instances — essentially a packaged server (OS + software + config) ready to boot.

🔹 What's Inside

  • 🖥️ Operating system (Linux, Windows)

  • ⚙️ Installed software & apps

  • 📊 Monitoring tools

  • 🔧 Custom configuration

Benefit: faster boot, faster deployment, no manual reinstalling.

🏗️ Types of AMIs

Type

Description

Best for

AWS-provided

e.g. Amazon Linux 2, maintained by AWS

Free, reliable starting point

Custom

Built from your own configured instance, you maintain it

Reusable, production-ready setups

Marketplace

Sold by vendors, comes with pre-installed tools (security, databases, etc.)

Ready-made specialized stacks

💡 You can even sell your own AMIs on the Marketplace.

🔄 How an AMI Is Created

  1. Launch an EC2 instance

  2. Customize it (apps, configs)

  3. Stop the instance (preserves data integrity)

  4. Create the AMI

  5. Launch new instances from it

Behind the scenes: creating an AMI automatically creates EBS snapshots — that's how your instance's data gets stored.

🌍 Cross-Region / Cross-AZ Use

AMIs are tied to a region, but you can copy an AMI to another region.

Example flow:

  1. Launch + customize an instance in ap-south-1a

  2. Convert it into an AMI

  3. Launch a new instance from that AMI in us-east-1b

Result: a replica of your instance running in a different AZ/region.

🧠 Key Takeaways

  • AMI = blueprint of an EC2 instance

  • Saves time via pre-packaging

  • Built on EBS snapshots internally

  • Enables fast scaling, consistent environments, and cross-AZ/region deployment