AWS::ECS::TaskDefinition HealthCheck - AWS CloudFormation

AWS::ECS::TaskDefinition HealthCheck

The HealthCheck property specifies an object representing a container health check. Health check parameters that are specified in a container definition override any Docker health checks that exist in the container image (such as those specified in a parent image or from the image's Dockerfile). This configuration maps to the HEALTHCHECK parameter of docker run.

Note

The Amazon ECS container agent only monitors and reports on the health checks specified in the task definition. Amazon ECS does not monitor Docker health checks that are embedded in a container image and not specified in the container definition. Health check parameters that are specified in a container definition override any Docker health checks that exist in the container image.

If a task is run manually, and not as part of a service, the task will continue its lifecycle regardless of its health status. For tasks that are part of a service, if the task reports as unhealthy then the task will be stopped and the service scheduler will replace it.

The following are notes about container health check support:

  • Container health checks require version 1.17.0 or greater of the Amazon ECS container agent. For more information, see Updating the Amazon ECS Container Agent.

  • Container health checks are supported for Fargate tasks if you are using platform version 1.1.0 or greater. For more information, see AWS Fargate Platform Versions.

  • Container health checks are not supported for tasks that are part of a service that is configured to use a Classic Load Balancer.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Command" : [ String, ... ], "Interval" : Integer, "Retries" : Integer, "StartPeriod" : Integer, "Timeout" : Integer }

YAML

Command: - String Interval: Integer Retries: Integer StartPeriod: Integer Timeout: Integer

Properties

Command

A string array representing the command that the container runs to determine if it is healthy. The string array must start with CMD to run the command arguments directly, or CMD-SHELL to run the command with the container's default shell.

When you use the AWS Management Console JSON panel, the AWS Command Line Interface, or the APIs, enclose the list of commands in double quotes and brackets.

[ "CMD-SHELL", "curl -f http://localhost/ || exit 1" ]

You don't include the double quotes and brackets when you use the AWS Management Console.

CMD-SHELL, curl -f http://localhost/ || exit 1

An exit code of 0 indicates success, and non-zero exit code indicates failure. For more information, see HealthCheck in the Create a container section of the Docker Remote API.

Required: No

Type: Array of String

Update requires: Replacement

Interval

The time period in seconds between each health check execution. You may specify between 5 and 300 seconds. The default value is 30 seconds.

Required: No

Type: Integer

Update requires: Replacement

Retries

The number of times to retry a failed health check before the container is considered unhealthy. You may specify between 1 and 10 retries. The default value is 3.

Required: No

Type: Integer

Update requires: Replacement

StartPeriod

The optional grace period to provide containers time to bootstrap before failed health checks count towards the maximum number of retries. You can specify between 0 and 300 seconds. By default, the startPeriod is off.

Note

If a health check succeeds within the startPeriod, then the container is considered healthy and any subsequent failures count toward the maximum number of retries.

Required: No

Type: Integer

Update requires: Replacement

Timeout

The time period in seconds to wait for a health check to succeed before it is considered a failure. You may specify between 2 and 60 seconds. The default value is 5.

Required: No

Type: Integer

Update requires: Replacement