# LoadBalancerProperty

The load balancer configuration to use with a service or task set.

When you add, update, or remove a load balancer configuration, Amazon ECS starts a new deployment with the updated Elastic Load Balancing configuration. This causes tasks to register to and deregister from load balancers.

We recommend that you verify this on a test environment before you update the Elastic Load Balancing configuration.

A service-linked role is required for services that use multiple target groups. For more information, see [Using service-linked roles](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/using-service-linked-roles.html) in the *Amazon Elastic Container Service Developer Guide* .

- Source: Generated code
- Type last changed: v2.93.0 · 23 Aug 2023

## Example

```ts
// The code below shows an example of how to instantiate this type.
// The values are placeholders you should change.
import { aws_ecs as ecs } from 'aws-cdk-lib';
const loadBalancerProperty: ecs.CfnTaskSet.LoadBalancerProperty = {
  containerName: 'containerName',
  containerPort: 123,
  targetGroupArn: 'targetGroupArn',
};
```

## Properties

- `containerName`: string — The name of the container (as it appears in a container definition) to associate with the load balancer.

  You need to specify the container name when configuring the target group for an Amazon ECS load balancer.

- `containerPort`: number — The port on the container to associate with the load balancer.

  This port must correspond to a `containerPort` in the task definition the tasks in the service are using. For tasks that use the EC2 launch type, the container instance they're launched on must allow ingress traffic on the `hostPort` of the port mapping.

- `targetGroupArn`: string — The full Amazon Resource Name (ARN) of the Elastic Load Balancing target group or groups associated with a service or task set.

  A target group ARN is only specified when using an Application Load Balancer or Network Load Balancer.

  For services using the `ECS` deployment controller, you can specify one or multiple target groups. For more information, see [Registering multiple target groups with a service](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/register-multiple-targetgroups.html) in the *Amazon Elastic Container Service Developer Guide* .

  For services using the `CODE_DEPLOY` deployment controller, you're required to define two target groups for the load balancer. For more information, see [Blue/green deployment with CodeDeploy](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/deployment-type-bluegreen.html) in the *Amazon Elastic Container Service Developer Guide* .

  > If your service's task definition uses the `awsvpc` network mode, you must choose `ip` as the target type, not `instance` . Do this when creating your target groups because tasks that use the `awsvpc` network mode are associated with an elastic network interface, not an Amazon EC2 instance. This network mode is required for the Fargate launch type.