Automating AMI Pipelines with EC2 Image Builder - Building and Testing Golden Images
Automate your golden AMI build pipeline from component creation and security hardening tests to multi-account distribution with EC2 Image Builder.
Overview of Image Builder
EC2 Image Builder is a service that automates the building, testing, and distribution of AMIs and container images. Instead of manually launching an EC2 instance, installing software, and creating an AMI, you define the entire process as a pipeline and run it automatically. With automated security testing and multi-account distribution, you can standardize golden images across your entire organization.
Recipes and Pipelines
An image recipe consists of a base AMI (Amazon Linux 2023, Ubuntu, etc.), build components (package installation, configuration file placement), and test components (boot verification, port checks). Components are defined in YAML and execute shell commands or PowerShell scripts. A pipeline runs the recipe on a schedule - for example, generating a freshly patched AMI every Monday. Distribution settings automatically copy the built AMI to other regions and accounts, sharing golden images across your entire organization.
Security Hardening and Multi-Account Distribution
Image Builder test components automatically run CIS benchmark and STIG compliance security checks, preventing the release of AMIs that fail to meet standards. AWSTOE (Image Builder TOE) components are written in YAML and declaratively define package installation, file placement, service configuration, and test execution. Distribution settings automatically share AMIs across multiple accounts and regions, with support for distribution by Organizations OU. AMI lifecycle policies automatically delete old images, keeping storage costs from spiraling due to AMI proliferation. EventBridge notifies you of pipeline success or failure and can trigger downstream deployment pipelines when a new AMI becomes available. For a deeper understanding of AMI automation patterns, related books on Amazon can be helpful.
Image Builder Pricing and Execution Optimization
Image Builder itself incurs no additional charges. Costs come from the EC2 instances and EBS volumes used during builds. Choose the right build instance type - t3.micro for lightweight recipes that don't require compilation, and m5.large for large software stacks. Schedule pipelines to run outside business hours when Spot Instances are more readily available to reduce costs. Align pipeline execution frequency with base AMI update cadence to avoid unnecessary builds. Leverage component caching to skip unchanged steps and shorten build times.
Summary
Image Builder automates the building, testing, and distribution of AMIs and container images. Automated security testing verifies CIS benchmark compliance, and distribution settings automatically share AMIs across multiple accounts and regions. Lifecycle policies automatically delete old images, and EventBridge triggers deployment pipelines when new AMIs become available.