Deploying ECS services

Now that you have successfully created an ECS service, let's examine how ECS manages new deployments of container applications. It is important to understand that ECS task definitions are immutable—that is, you cannot modify a task definition once it has been created, and instead you need to either create a completely new task definition or create a revision of your current task definition, which you can think of as a new version of a given task definition.

ECS defines the logical name of an ECS task definition as the family, and a given revision of an ECS task definition is expressed in the form family:revision—for example, my-task-definition:3 refers to revision 3 from the my-task-definition family.

This means that in order to deploy a new version of a container application, you need to perform a couple of steps:

1. Create a new revision of your ECS task definition with configuration settings that have been changed for the new version of your application. This often will...