How to set an alarm not to trigger action after autoscaling

Question

I have a problem setting my autoscaling group. I have created an alarm that when triggered makes the autoscaling add a new EC2 instance to it. The autoscaling has 200 seconds of Default Cooldown period, but the alarm keeps recording data during that time and is triggered again. That makes the autoscaling group launch another machine and end up entering a loop that makes the group raise all the available machines.

How can I configure the autoscaling group so that it ignores the second triggered alarm? Is there any point about the configuration that I seem to be missing? Thanks in advance.

EDIT:

These are the metrics and scaling policies that trigger my group:

And this is the reason why I think that the autoscaling is still receiving alarms. Because terminations and launchings overlap in time.

Answer 1

I am not sure which type of health check you are using but there is a condition called "grace period"

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

https://docs.aws.amazon.com/autoscaling/ec2/userguide/healthcheck.html

That can be the configuration that you are missing

AWS autoscale ELB status checks grace period