title: What's the difference between AWS ASG Cooldown Period and health check grace period?
body: <p>AWS Autoscaling has 2 concepts:</p>
  
  <ul>
  <li><strong>Cooldown period</strong>: From AWS documentation: the cooldown period helps to ensure that your Auto Scaling group doesn't launch or terminate additional instances before the previous scaling activity takes effect. You can configure the length of time based on your instance warmup period or other application needs. Details are <a href="https://docs.aws.amazon.com/autoscaling/ec2/userguide/Cooldown.html" rel="noreferrer">here</a>.</li>
  <li><strong>Health check grace period</strong>: From AWS documentation: frequently, an Auto Scaling instance that has just come into service needs to warm up before it can pass the health check. Amazon EC2 Auto Scaling waits until the health check grace period ends before checking the health status of the instance. Details are <a href="https://docs.aws.amazon.com/autoscaling/ec2/userguide/healthcheck.html#health-check-grace-period" rel="noreferrer">here</a>.</li>
  </ul>
  
  <p>But I can't figure out the difference between them. Can somebody help?</p>
  
  <p>Thanks in advance.</p>