# Prerequisites
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To complete this tutorial, you must first:
+  Complete steps 2 and 3 in [Getting started with CodeDeploy](getting-started-codedeploy.md). 
+  Create an Application Load Balancer configured with two target groups and one listener. For information about creating a load balancer using the console, see [Set up a load balancer, target groups, and listeners for CodeDeploy Amazon ECS deployments](deployment-groups-create-load-balancer-for-ecs.md). For information about creating a load balancer using the AWS CLI, see [Step 1: Create an Application Load Balancer](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/create-blue-green.html#create-blue-green-loadbalancer) in the *Amazon Elastic Container Service User Guide*. When you create your load balancer, make a note of the following for this tutorial: 
  +  The name of your load balancer. 
  +  The names of your target groups. 
  +  The port used by your load balancer's listener. 
+  Create an Amazon ECS cluster and service. For more information, see steps 2, 3, and 4 in [ Tutorial: Creating a service using a blue/green deployment](https://docs.aws.amazon.com/AmazonECS/latest/developerguide/create-blue-green.html) in the *Amazon Elastic Container Service User Guide*. Make a note of the following for this tutorial: 
  +  The name of your Amazon ECS cluster. 
  +  The ARN of the the task definition used by your Amazon ECS service. 
  +  The name of the the container used by your Amazon ECS service. 
+  Create an Amazon S3 bucket for your AppSpec file.