AWS SDK Version 2 for .NET
API Reference

AWS services or capabilities described in AWS Documentation may vary by region/location. Click Getting Started with Amazon AWS to see specific differences applicable to the China (Beijing) Region.

.NET Framework 3.5
Modifies the desired count, deployment configuration, or task definition used in a service.

You can add to or subtract from the number of instantiations of a task definition in a service by specifying the cluster that the service is running in and a new desiredCount parameter.

You can use UpdateService to modify your task definition and deploy a new version of your service.

You can also update the deployment configuration of a service. When a deployment is triggered by updating the task definition of a service, the service scheduler uses the deployment configuration parameters, minimumHealthyPercent and maximumPercent, to determine the deployment strategy.

If the minimumHealthyPercent is below 100%, the scheduler can ignore the desiredCount temporarily during a deployment. For example, if your service has a desiredCount of four tasks, a minimumHealthyPercent of 50% allows the scheduler to stop two existing tasks before starting two new tasks. Tasks for services that do not use a load balancer are considered healthy if they are in the RUNNING state; tasks for services that do use a load balancer are considered healthy if they are in the RUNNING state and the container instance it is hosted on is reported as healthy by the load balancer.

The maximumPercent parameter represents an upper limit on the number of running tasks during a deployment, which enables you to define the deployment batch size. For example, if your service has a desiredCount of four tasks, a maximumPercent value of 200% starts four new tasks before stopping the four older tasks (provided that the cluster resources required to do this are available).

When UpdateService stops a task during a deployment, the equivalent of

is issued to the containers running in the task. This results in a SIGTERM and a 30-second timeout, after which SIGKILL is sent and the containers are forcibly stopped. If the container handles the SIGTERM gracefully and exits within 30 seconds from receiving it, no SIGKILL is sent.

When the service scheduler launches new tasks, it attempts to balance them across the Availability Zones in your cluster with the following logic:

Namespace: Amazon.ECS
Assembly: AWSSDK.dll
Version: (assembly version)


public virtual UpdateServiceResponse UpdateService(
         UpdateServiceRequest request


Type: Amazon.ECS.Model.UpdateServiceRequest

Container for the necessary parameters to execute the UpdateService service method.

Return Value
Type: Amazon.ECS.Model.UpdateServiceResponse
The response from the UpdateService service method, as returned by ECS.


ClientException These errors are usually caused by a client action, such as using an action or resource on behalf of a user that doesn't have permission to use the action or resource, or specifying an identifier that is not valid.
ClusterNotFoundException The specified cluster could not be found. You can view your available clusters with ListClusters. Amazon ECS clusters are region-specific.
InvalidParameterException The specified parameter is invalid. Review the available parameters for the API request.
ServerException These errors are usually caused by a server issue.
ServiceNotActiveException The specified service is not active. You cannot update a service that is not active. If you have previously deleted a service, you can re-create it with CreateService.
ServiceNotFoundException The specified service could not be found. You can view your available services with ListServices. Amazon ECS services are cluster-specific and region-specific.

Version Information

.NET Framework:
Supported in: 4.5, 4.0, 3.5