Create Reusable Server Images with AWS AMI

When working with Amazon EC2, launching an instance is only part of the process. What happens when you need to recreate that instance multiple times, across environments, or even across regions? That’s where Amazon Machine Images (AMIs) come in.

In this article, we’ll look at how AWS AMIs work, why you should use them, and how to create and manage your own custom AMIs to streamline your infrastructure automation.

What Is an AMI?

An Amazon Machine Image (AMI) is a snapshot of an EC2 instance that includes:

• The operating system

• Installed software and packages

• Application code or configuration

• EBS volume snapshots

• Launch permissions and settings

You use AMIs to launch new EC2 instances that replicate the setup of the original system—consistently and reliably.

Why Use an AMI?

Using AMIs enables you to:

• Standardize environments across dev, test, and prod.

• Speed up instance launches with pre-baked configurations.

• Version your infrastructure similar to how you version your code.

• Enable scaling via Auto Scaling Groups using a consistent base image.

• Support immutable infrastructure by redeploying via fresh AMIs

How to Create a Custom AMI

Let’s walk through creating your own AMI from an existing EC2 instance.

Step 1: Launch and Configure an EC2 Instance

Start by setting up an EC2 instance as you normally would:

# Example: Launch an Ubuntu instance
aws ec2 run-instances \
  --image-id ami-xxxxxxx \
  --instance-type t2.micro \
  --key-name my-key \
  --security-groups my-sg

Install any software or make any configuration changes required.

Step 2: Create the AMI from the Instance

Once your instance is ready:

1. Open the EC2 Console.

2. Select your instance > Actions > Image and templates > Create Image.

3. Provide an image name and optional description.

4. Click Create Image.

AWS will create an AMI and register it for future use. This may take a few minutes.

Launching New Instances from Your AMI

You can now launch new EC2 instances using your custom AMI either via the console or CLI:

aws ec2 run-instances \
  --image-id ami-0abcd1234example \
  --instance-type t3.micro \
  --key-name my-key \
  --security-groups my-sg

This will create a new instance with all your configurations and software already in place.

Copying AMIs Across Regions

AMIs are region-specific. To use an AMI in another region, you need to copy it:

aws ec2 copy-image \
  --source-image-id ami-12345678 \
  --source-region us-east-1 \
  --region eu-west-1 \
  --name "MyCopiedAMI"

Common Use Cases

Wrapping Up

AMIs are a core part of AWS infrastructure strategy. Whether you're scaling up web servers, running data processing pipelines, or managing fleets of microservices, building reusable AMIs helps ensure your deployments are fast, consistent, and repeatable.

By incorporating AMI creation into your workflow, you take one step closer to fully automated, immutable infrastructure.