AWS::ECS::Service DeploymentConfiguration - AWS CloudFormation
SyntaxPropertiesSee also

AWS::ECS::Service DeploymentConfiguration

Optional deployment parameters that control how many tasks run during a deployment and the ordering of stopping and starting tasks.

Syntax

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

Properties

Alarms

Information about the CloudWatch alarms.

Required: No

Type: DeploymentAlarms

Update requires: No interruption

DeploymentCircuitBreaker
Note

The deployment circuit breaker can only be used for services using the rolling update (ECS) deployment type.

The deployment circuit breaker determines whether a service deployment will fail if the service can't reach a steady state. If you use the deployment circuit breaker, a service deployment will transition to a failed state and stop launching new tasks. If you use the rollback option, when a service deployment fails, the service is rolled back to the last deployment that completed successfully. For more information, see Rolling update in the Amazon Elastic Container Service Developer Guide

Required: No

Type: DeploymentCircuitBreaker

Update requires: No interruption

MaximumPercent

If a service is using the rolling update (ECS) deployment type, the maximumPercent parameter represents an upper limit on the number of your service's tasks that are allowed in the RUNNING or PENDING state during a deployment, as a percentage of the desiredCount (rounded down to the nearest integer). This parameter enables you to define the deployment batch size. For example, if your service is using the REPLICA service scheduler and has a desiredCount of four tasks and a maximumPercent value of 200%, the scheduler may start four new tasks before stopping the four older tasks (provided that the cluster resources required to do this are available). The default maximumPercent value for a service using the REPLICA service scheduler is 200%.

If a service is using either the blue/green (CODE_DEPLOY) or EXTERNAL deployment types, and tasks in the service use the EC2 launch type, the maximum percent value is set to the default value. The maximum percent value is used to define the upper limit on the number of the tasks in the service that remain in the RUNNING state while the container instances are in the DRAINING state.

Note

You can't specify a custom maximumPercent value for a service that uses either the blue/green (CODE_DEPLOY) or EXTERNAL deployment types and has tasks that use the EC2 launch type.

If the tasks in the service use the Fargate launch type, the maximum percent value is not used, although it is returned when describing your service.

Required: No

Type: Integer

Update requires: No interruption

MinimumHealthyPercent

If a service is using the rolling update (ECS) deployment type, the minimumHealthyPercent represents a lower limit on the number of your service's tasks that must remain in the RUNNING state during a deployment, as a percentage of the desiredCount (rounded up to the nearest integer). This parameter enables you to deploy without using additional cluster capacity. For example, if your service has a desiredCount of four tasks and a minimumHealthyPercent of 50%, the service scheduler may stop two existing tasks to free up cluster capacity before starting two new tasks.

For services that do not use a load balancer, the following should be noted:

  • A service is considered healthy if all essential containers within the tasks in the service pass their health checks.

  • If a task has no essential containers with a health check defined, the service scheduler will wait for 40 seconds after a task reaches a RUNNING state before the task is counted towards the minimum healthy percent total.

  • If a task has one or more essential containers with a health check defined, the service scheduler will wait for the task to reach a healthy status before counting it towards the minimum healthy percent total. A task is considered healthy when all essential containers within the task have passed their health checks. The amount of time the service scheduler can wait for is determined by the container health check settings.

For services that do use a load balancer, the following should be noted:

  • If a task has no essential containers with a health check defined, the service scheduler will wait for the load balancer target group health check to return a healthy status before counting the task towards the minimum healthy percent total.

  • If a task has an essential container with a health check defined, the service scheduler will wait for both the task to reach a healthy status and the load balancer target group health check to return a healthy status before counting the task towards the minimum healthy percent total.

The default value for a replica service for minimumHealthyPercent is 100%. The default minimumHealthyPercent value for a service using the DAEMON service schedule is 0% for the AWS CLI, the AWS SDKs, and the APIs and 50% for the AWS Management Console.

The minimum number of healthy tasks during a deployment is the desiredCount multiplied by the minimumHealthyPercent/100, rounded up to the nearest integer value.

If a service is using either the blue/green (CODE_DEPLOY) or EXTERNAL deployment types and is running tasks that use the EC2 launch type, the minimum healthy percent value is set to the default value. The minimum healthy percent value is used to define the lower limit on the number of the tasks in the service that remain in the RUNNING state while the container instances are in the DRAINING state.

Note

You can't specify a custom minimumHealthyPercent value for a service that uses either the blue/green (CODE_DEPLOY) or EXTERNAL deployment types and has tasks that use the EC2 launch type.

If a service is using either the blue/green (CODE_DEPLOY) or EXTERNAL deployment types and is running tasks that use the Fargate launch type, the minimum healthy percent value is not used, although it is returned when describing your service.

Required: No

Type: Integer

Update requires: No interruption

See also