Amazon EC2 Container Service

Updates the Amazon ECS container agent on a specified container instance. Updating the Amazon ECS container agent doesn't interrupt running tasks or services on the container instance. The process for updating the agent differs depending on whether your container instance was launched with the Amazon ECS-optimized AMI or another operating system. The UpdateContainerAgent API isn't supported for container instances using the Amazon ECS-optimized Amazon Linux 2 (arm64) AMI. To update the container agent, you can update the ecs-init package. This updates the agent. For more information, see Updating the Amazon ECS container agent in the Amazon Elastic Container Service Developer Guide. Agent updates with the UpdateContainerAgent API operation do not apply to Windows container instances. We recommend that you launch new container instances to update the agent version in your Windows clusters. The UpdateContainerAgent API requires an Amazon ECS-optimized AMI or Amazon Linux AMI with the ecs-init service installed and running. For help updating the Amazon ECS container agent on other operating systems, see Manually updating the Amazon ECS container agent in the Amazon Elastic Container Service Developer Guide.

Modifies the status of an Amazon ECS container instance. Once a container instance has reached an ACTIVE state, you can change the status of a container instance to DRAINING to manually remove an instance from a cluster, for example to perform system updates, update the Docker daemon, or scale down the cluster size. A container instance can't be changed to DRAINING until it has reached an ACTIVE status. If the instance is in any other status, an error will be received. When you set a container instance to DRAINING, Amazon ECS prevents new tasks from being scheduled for placement on the container instance and replacement service tasks are started on other container instances in the cluster if the resources are available. Service tasks on the container instance that are in the PENDING state are stopped immediately. Service tasks on the container instance that are in the RUNNING state are stopped and replaced according to the service's deployment configuration parameters, minimumHealthyPercent and maximumPercent. You can change the deployment configuration of your service using UpdateService. If minimumHealthyPercent is below 100%, the scheduler can ignore desiredCount temporarily during task replacement. For example, desiredCount is four tasks, a minimum of 50% allows the scheduler to stop two existing tasks before starting two new tasks. If the minimum is 100%, the service scheduler can't remove existing tasks until the replacement tasks are considered healthy. Tasks for services that do not use a load balancer are considered healthy if they're in the RUNNING state. Tasks for services that use a load balancer are considered healthy if they're in the RUNNING state and are reported as healthy by the load balancer. The maximumPercent parameter represents an upper limit on the number of running tasks during task replacement. You can use this to define the replacement batch size. For example, if desiredCount is four tasks, a maximum of 200% starts four new tasks before stopping the four tasks to be drained, provided that the cluster resources required to do this are available. If the maximum is 100%, then replacement tasks can't start until the draining tasks have stopped. Any PENDING or RUNNING tasks that do not belong to a service aren't affected. You must wait for them to finish or stop them manually. A container instance has completed draining when it has no more RUNNING tasks. You can verify this using ListTasks. When a container instance has been drained, you can set a container instance to ACTIVE status and once it has reached that status the Amazon ECS scheduler can begin scheduling tasks on the instance again.

Modifies the parameters of a service. For services using the rolling update (ECS) you can update the desired count, deployment configuration, network configuration, load balancers, service registries, enable ECS managed tags option, propagate tags option, task placement constraints and strategies, and task definition. When you update any of these parameters, Amazon ECS starts new tasks with the new configuration. For services using the blue/green (CODE_DEPLOY) deployment controller, only the desired count, deployment configuration, health check grace period, task placement constraints and strategies, enable ECS managed tags option, and propagate tags can be updated using this API. If the network configuration, platform version, task definition, or load balancer need to be updated, create a new CodeDeploy deployment. For more information, see CreateDeployment in the CodeDeploy API Reference. For services using an external deployment controller, you can update only the desired count, task placement constraints and strategies, health check grace period, enable ECS managed tags option, and propagate tags option, using this API. If the launch type, load balancer, network configuration, platform version, or task definition need to be updated, create a new task set For more information, see CreateTaskSet. 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. If you have updated the Docker image of your application, you can create a new task definition with that image and deploy it to your service. The service scheduler uses the minimum healthy percent and maximum percent parameters (in the service's deployment configuration) to determine the deployment strategy. If your updated Docker image uses the same tag as what is in the existing task definition for your service (for example, my_image:latest), you don't need to create a new revision of your task definition. You can update the service using the forceNewDeployment option. The new tasks launched by the deployment pull the current image/tag combination from your repository when they start. 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 minimumHealthyPercent is below 100%, the scheduler can ignore desiredCount temporarily during a deployment. For example, if desiredCount is four tasks, a minimum of 50% allows the scheduler to stop two existing tasks before starting two new tasks. Tasks for services that don't use a load balancer are considered healthy if they're in the RUNNING state. Tasks for services that use a load balancer are considered healthy if they're in the RUNNING state and are reported as healthy by the load balancer. The maximumPercent parameter represents an upper limit on the number of running tasks during a deployment. You can use it to define the deployment batch size. For example, if desiredCount is four tasks, a maximum 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 docker stop is issued to the containers running in the task. This results in a SIGTERM and a 30-second timeout. After this, 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 determines task placement in your cluster with the following logic. Determine which of the container instances in your cluster can support your service's task definition. For example, they have the required CPU, memory, ports, and container instance attributes. By default, the service scheduler attempts to balance tasks across Availability Zones in this manner even though you can choose a different placement strategy. Sort the valid container instances by the fewest number of running tasks for this service in the same Availability Zone as the instance. For example, if zone A has one running service task and zones B and C each have zero, valid container instances in either zone B or C are considered optimal for placement. Place the new service task on a valid container instance in an optimal Availability Zone (based on the previous steps), favoring container instances with the fewest number of running tasks for this service. When the service scheduler stops running tasks, it attempts to maintain balance across the Availability Zones in your cluster using the following logic: Sort the container instances by the largest number of running tasks for this service in the same Availability Zone as the instance. For example, if zone A has one running service task and zones B and C each have two, container instances in either zone B or C are considered optimal for termination. Stop the task on a container instance in an optimal Availability Zone (based on the previous steps), favoring container instances with the largest number of running tasks for this service. You must have a service-linked role when you update any of the following service properties. If you specified a custom role when you created the service, Amazon ECS automatically replaces the roleARN associated with the service with the ARN of your service-linked role. For more information, see Service-linked roles in the Amazon Elastic Container Service Developer Guide. loadBalancers, serviceRegistries

Modifies which task set in a service is the primary task set. Any parameters that are updated on the primary task set in a service will transition to the service. This is used when a service uses the EXTERNAL deployment controller type. For more information, see Amazon ECS Deployment Types in the Amazon Elastic Container Service Developer Guide.

Updates the protection status of a task. You can set protectionEnabled to true to protect your task from termination during scale-in events from Service Autoscaling or deployments. Task-protection, by default, expires after 2 hours at which point Amazon ECS clears the protectionEnabled property making the task eligible for termination by a subsequent scale-in event. You can specify a custom expiration period for task protection from 1 minute to up to 2,880 minutes (48 hours). To specify the custom expiration period, set the expiresInMinutes property. The expiresInMinutes property is always reset when you invoke this operation for a task that already has protectionEnabled set to true. You can keep extending the protection expiration period of a task by invoking this operation repeatedly. To learn more about Amazon ECS task protection, see Task scale-in protection in the Amazon Elastic Container Service Developer Guide . This operation is only supported for tasks belonging to an Amazon ECS service. Invoking this operation for a standalone task will result in an TASK_NOT_VALID failure. For more information, see API failure reasons. If you prefer to set task protection from within the container, we recommend using the Task scale-in protection endpoint.

Modifies a task set. This is used when a service uses the EXTERNAL deployment controller type. For more information, see Amazon ECS Deployment Types in the Amazon Elastic Container Service Developer Guide.