# Updating an Amazon ECS service
<a name="update-service-console-v2"></a>

After you create a service, there are times when you might need to update the service parameters, for example the number of tasks.

When you update a service that uses Amazon ECS circuit breaker, Amazon ECS creates a service deployment and a service revision. These resources allow you to view detailed information about the service history. For more information, see [View service history using Amazon ECS service deployments](service-deployment.md).

## Prerequisites
<a name="update-service-prerequisites"></a>

Before updating a service, verify which service parameters can be changed for your deployment type. For a complete list of changeable parameters, see [Update Amazon ECS service parameters](update-service-parameters.md).

## Procedure
<a name="update-service-procedure"></a>

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#### [ Console ]

1. Open the console at [https://console.aws.amazon.com/ecs/v2](https://console.aws.amazon.com/ecs/v2).

1. On the **Clusters** page, choose the cluster.

1. On the cluster details page, in the **Services** section, select the check box next to the service, and then choose **Update**.

1. To have your service start a new deployment, select **Force new deployment**.

1. For **Task definition**, choose the task definition family and revision.
**Important**  
The console validates that the selected task definition family and revision are compatible with the defined compute configuration. If you receive a warning, verify both your task definition compatibility and the compute configuration that you selected.

1. If you chose **Replica**, for **Desired tasks**, enter the number of tasks to launch and maintain in the service.

1. If you chose **Replica**, to have Amazon ECS monitor the distribution of tasks across Availability Zones, and redistribute them when there is an imbalance, under **Availability Zone service rebalancing**, select **Availability Zone service rebalancing**.

1. For **Min running tasks**, enter the lower limit on the number of tasks in the service that must remain in the `RUNNING` state during a deployment, as a percentage of the desired number of tasks (rounded up to the nearest integer). For more information, see [Deployment configuration](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/service_definition_parameters.html#sd-deploymentconfiguration).

1. For **Max running tasks**, enter the upper limit on the number of tasks in the service that are allowed in the `RUNNING` or `PENDING` state during a deployment, as a percentage of the desired number of tasks (rounded down to the nearest integer).

1. To configure how tasks are deployed for your service, expand **Deployment options** and then configure your options.

   1. For **Deployment controller type**, specify the service deployment controller. The Amazon ECS console supports the following controller types: `ECS`.

   1. For **Deployment strategy**, choose the strategy used by Amazon ECS to deploy new versions of the service.

   1. Depending on the choice of **Deployment strategy**, do the following:    
[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AmazonECS/latest/developerguide/update-service-console-v2.html)

   1. To run Lambda functions for a lifecycle stage, under **Deployment lifecyce hooks** do the following for each unique Lambda function:

      1. Choose **Add**.

         Repeat for every unique function you want to run.

      1. For **Lambda function**, enter the function name.

      1. For **Role**, choose the role that you created in the prerequisites with the blue/green permissions.

         For more information, see [Permissions required for Lambda functions in Amazon ECS blue/green deployments](blue-green-permissions.md).

      1. For **Lifecycle stages**, select the stages the Lambda function runs.

      1.  (Optional) For **Hook details**, enter a key value pair that provides information about the hook.

1. To configure how Amazon ECS detects and handles deployment failures, expand **Deployment failure detection**, and then choose your options. 

   1. To stop a deployment when the tasks cannot start, select **Use the Amazon ECS deployment circuit breaker**.

      To have the software automatically roll back the deployment to the last completed deployment state when the deployment circuit breaker sets the deployment to a failed state, select **Rollback on failures**.

   1. To stop a deployment based on application metrics, select **Use CloudWatch alarm(s)**. Then, from **CloudWatch alarm name**, choose the alarms. To create a new alarm, go to the CloudWatch console.

      To have the software automatically roll back the deployment to the last completed deployment state when a CloudWatch alarm sets the deployment to a failed state, select **Rollback on failures**.

1. To change the compute options, expand **Compute configuration**, and then do the following: 

   1. For services on AWS Fargate, for **Platform version**, choose the new version.

   1. For services that use a capacity provider strategy, for **Capacity provider strategy**, do the following:
      + To add an additional capacity provider, choose **Add more**. Then, for **Capacity provider**, choose the capacity provider.
      + To remove a capacity provider, to the right of the capacity provider, choose **Remove**.

      A service that's using an Auto Scaling group capacity provider can't be updated to use a Fargate capacity provider. A service that's using a Fargate capacity provider can't be updated to use an Auto Scaling group capacity provider.

1. (Optional) To configure service Auto Scaling, expand **Service auto scaling**, and then specify the following parameters.To use predicte auto scaling, which looks at past load data from traffic flows, configure it after you create the service. For more information, see [Use historical patterns to scale Amazon ECS services with predictive scaling](predictive-auto-scaling.md).

   1. To use service auto scaling, select **Service auto scaling**.

   1. For **Minimum number of tasks**, enter the lower limit of the number of tasks for service auto scaling to use. The desired count will not go below this count.

   1. For **Maximum number of tasks**, enter the upper limit of the number of tasks for service auto scaling to use. The desired count will not go above this count.

   1. Choose the policy type. Under **Scaling policy type**, choose one of the following options.    
[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AmazonECS/latest/developerguide/update-service-console-v2.html)

1. (Optional) To use Service Connect, select **Turn on Service Connect**, and then specify the following:

   1. Under **Service Connect configuration**, specify the client mode.
      + If your service runs a network client application that only needs to connect to other services in the namespace, choose **Client side only**.
      + If your service runs a network or web service application and needs to provide endpoints for this service, and connects to other services in the namespace, choose **Client and server**.

   1. To use a namespace that is not the default cluster namespace, for **Namespace**, choose the service namespace. This can be a namespace created separately in the same AWS Region in your AWS account or a namespace in the same Region that is shared with your account using AWS Resource Access Manager (AWS RAM). For more information about shared AWS Cloud Map namespaces, see [Cross-account AWS Cloud Map namespace sharing](https://docs.aws.amazon.com/cloud-map/latest/dg/sharing-namespaces.html) in the *AWS Cloud Map Developer Guide*

   1. (Optional) Specify a log configuration. Select **Use log collection**. The default option sends container logs to CloudWatch Logs. The other log driver options are configured using AWS FireLens. For more information, see [Send Amazon ECS logs to an AWS service or AWS Partner](using_firelens.md).

      The following describes each container log destination in more detail.
      + **Amazon CloudWatch** – Configure the task to send container logs to CloudWatch Logs. The default log driver options are provided, which create a CloudWatch log group on your behalf. To specify a different log group name, change the driver option values.
      + **Amazon Data Firehose** – Configure the task to send container logs to Firehose. The default log driver options are provided, which send logs to a Firehose delivery stream. To specify a different delivery stream name, change the driver option values.
      + **Amazon Kinesis Data Streams** – Configure the task to send container logs to Kinesis Data Streams. The default log driver options are provided, which send logs to an Kinesis Data Streams stream. To specify a different stream name, change the driver option values.
      + **Amazon OpenSearch Service** – Configure the task to send container logs to an OpenSearch Service domain. The log driver options must be provided. 
      + **Amazon S3** – Configure the task to send container logs to an Amazon S3 bucket. The default log driver options are provided, but you must specify a valid Amazon S3 bucket name.

   1. To enable access logs, follow these steps:

      1. Expand **Access log configuration**. For **Format**, choose either **JSON** or `TEXT`.

      1. To include query parameters in access logs, select **Include query parameters**.
**Note**  
To disable access logs, for **Format**, choose **None**.

1. If your task uses a data volume that's compatible with configuration at deployment, you can configure the volume by expanding **Volume**.

   The volume name and volume type are configured when you create a task definition revision and can't be changed when you update a service. To update the volume name and type, you must create a new task definition revision and update the service by using the new revision.    
[\[See the AWS documentation website for more details\]](http://docs.aws.amazon.com/AmazonECS/latest/developerguide/update-service-console-v2.html)

1. (Optional) To help identify your service, expand the **Tags** section, and then configure your tags.
   + [Add a tag] Choose **Add tag**, and do the following:
     + For **Key**, enter the key name.
     + For **Value**, enter the key value.
   + [Remove a tag] Next to the tag, choose **Remove tag**.

1. Choose **Update**.

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#### [ AWS CLI ]
+ Run `update-service`. For information about running the command, see [update-service](https://docs.aws.amazon.com/cli/latest/reference/ecs/update-service.html) in the AWS Command Line Interface Reference. 

  The following `update-service` example updates the desired task count of the service `my-http-service` to 2.

  Replace the *user-input* with your values.

  ```
  aws ecs update-service \
      --cluster MyCluster \
      --service my-http-service \
      --desired-count 2
  ```

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## Next steps
<a name="update-service-next-steps"></a>

Track your deployment and view your service history for services that Amazon ECS circuit breaker. For more information, see [View service history using Amazon ECS service deployments](service-deployment.md).