How Golden AMIs Enable Safer, Consistent App Deployments on AWS Auto Scaling Groups

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A developer has detailed a deployment workflow using Golden AMIs to update applications running in AWS EC2 Auto Scaling Groups without manually reconfiguring individual servers. The process involves updating a single EC2 instance, verifying application health, and creating a new AMI that serves as the standard image for all future instances. A new Launch Template version is then created with the updated AMI, and AWS Instance Refresh gradually replaces old instances with new ones while maintaining service availability. The approach minimises configuration drift by ensuring every instance in the group is launched from an identical, pre-tested image. Rollbacks are simplified as well, requiring only a revert to the previous Launch Template version followed by another Instance Refresh cycle.

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