When it comes to EC2 instances termination logic, or scale-in events, Amazon EC2 follows a well-defined process to efficiently manage and optimize resource allocation. The termination logic primarily revolves around removing instances from an Auto Scaling group in response to scaling policies or events.
EC2 instances are terminated based on configurable rules and algorithms that consider factors like instance health, availability zones, and instance lifecycle. To maximize cost-effectiveness and resource utilization, EC2 instances are selected for termination based on the scaling policy defined, prioritizing instances that are overprovisioned or underutilized.
Additionally, the termination process aims to distribute instances across availability zones to maintain high availability while ensuring an even workload distribution. Overall, EC2 instances termination logic emphasizes efficient resource management and scaling optimization within the Auto Scaling environment.
Oldest Launch Configuration > Closest to the Billing Hour > Random Instance
