DeploymentConfiguration
Optional deployment parameters that control how many tasks run during a deployment and the ordering of stopping and starting tasks.
Contents
- alarms
-
Information about the CloudWatch alarms.
Type: DeploymentAlarms object
Required: No
- 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
Type: DeploymentCircuitBreaker object
Required: No
- maximumPercent
-
If a service is using the rolling update (
ECS
) deployment type, themaximumPercent
parameter represents an upper limit on the number of your service's tasks that are allowed in theRUNNING
orPENDING
state during a deployment, as a percentage of thedesiredCount
(rounded down to the nearest integer). This parameter enables you to define the deployment batch size. For example, if your service is using theREPLICA
service scheduler and has adesiredCount
of four tasks and amaximumPercent
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 defaultmaximumPercent
value for a service using theREPLICA
service scheduler is 200%.The Amazon ECS scheduler uses this parameter to replace unhealthy tasks by starting replacement tasks first and then stopping the unhealthy tasks, as long as cluster resources for starting replacement tasks are available. For more information about how the scheduler replaces unhealthy tasks, see Amazon ECS services.
If a service is using either the blue/green (
CODE_DEPLOY
) orEXTERNAL
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 theRUNNING
state while the container instances are in theDRAINING
state.Note
You can't specify a custom
maximumPercent
value for a service that uses either the blue/green (CODE_DEPLOY
) orEXTERNAL
deployment types and has tasks that use the EC2 launch type.If the service uses either the blue/green (
CODE_DEPLOY
) orEXTERNAL
deployment types, and the tasks in the service use the Fargate launch type, the maximum percent value is not used. The value is still returned when describing your service.Type: Integer
Required: No
- minimumHealthyPercent
-
If a service is using the rolling update (
ECS
) deployment type, theminimumHealthyPercent
represents a lower limit on the number of your service's tasks that must remain in theRUNNING
state during a deployment, as a percentage of thedesiredCount
(rounded up to the nearest integer). This parameter enables you to deploy without using additional cluster capacity. For example, if your service has adesiredCount
of four tasks and aminimumHealthyPercent
of 50%, the service scheduler may stop two existing tasks to free up cluster capacity before starting two new tasks.If any tasks are unhealthy and if
maximumPercent
doesn't allow the Amazon ECS scheduler to start replacement tasks, the scheduler stops the unhealthy tasks one-by-one — using theminimumHealthyPercent
as a constraint — to clear up capacity to launch replacement tasks. For more information about how the scheduler replaces unhealthy tasks, see Amazon ECS services .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 defaultminimumHealthyPercent
value for a service using theDAEMON
service schedule is 0% for the Amazon CLI, the Amazon SDKs, and the APIs and 50% for the Amazon Management Console.The minimum number of healthy tasks during a deployment is the
desiredCount
multiplied by theminimumHealthyPercent
/100, rounded up to the nearest integer value.If a service is using either the blue/green (
CODE_DEPLOY
) orEXTERNAL
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 theRUNNING
state while the container instances are in theDRAINING
state.Note
You can't specify a custom
minimumHealthyPercent
value for a service that uses either the blue/green (CODE_DEPLOY
) orEXTERNAL
deployment types and has tasks that use the EC2 launch type.If a service is using either the blue/green (
CODE_DEPLOY
) orEXTERNAL
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.Type: Integer
Required: No
-
See Also
For more information about using this API in one of the language-specific Amazon SDKs, see the following: