AWS Auto Scaling Group — EC2 Type HealthCheck Vs ELB Type HealthCheck

This article is just a simplification of what Amazon states in it’s AWS documentation of ASG.

There are two types of health checks available while configuring AWS Auto-scaling group and below is how they are different.

1. EC2 — This is very basic. The decision whether the instance is healthy or not is made based on the health of the EC2 instance itself. Imagine you have a windows machine and your aim is to install microsoft office on it. In this scenario, EC2 health check just checks if windows health is alright, but not if microsoft office is working or not.
2. ELB — This is the preferred type of Health Check. When you select ELB, ASG does all that mentioned above for EC2 AND it also peroforms health check configured for ELB.