healthCheckGracePeriodSeconds

The period of time, in seconds, that the Amazon ECS service scheduler ignores unhealthy Elastic Load Balancing target health checks after a task has first started. This is only used when your service is configured to use a load balancer. If your service has a load balancer defined and you don't specify a health check grace period value, the default value of `0` is used. If you do not use an Elastic Load Balancing, we recommend that you use the `startPeriod` in the task definition health check parameters. For more information, see Health check. If your service's tasks take a while to start and respond to Elastic Load Balancing health checks, you can specify a health check grace period of up to 2,147,483,647 seconds (about 69 years). During that time, the Amazon ECS service scheduler ignores health check status. This grace period can prevent the service scheduler from marking tasks as unhealthy and stopping them before they have time to come up.