AWS Compute Blog

Amazon ECS launches agent updates, task definition deregistration, environment variable overrides

We are pleased to announce the availability of several of our most requested features:

Agent Update
You now have an automated way to update the ECS agents that run on the EC2 instances in your clusters. The agent is the interface between ECS and Docker that enables operations such as starting containers and reporting status. This improvement simplifies cluster management and makes it easier to adopt new features that require agent updates. You can also now view the Docker version through the console, AWS CLI, or AWS SDK improving your ability to identify out of date Docker versions. See the documentation to find out how.

Task Definition Deregistration
You can now deregister task definitions that are no longer needed. Task definitions are a description of an application that contains one or more container definitions. You create new task definition revisions as you update your application. You can now deregister task definitions to remove outdated revisions. You can also sort task definitions from oldest to newest or newest to oldest, making it easy to find specific task definition revisions. See the documentation for more details.

Environment Variable Overrides
You can now override task definition environment variables when running a task. Task definitions can include environment variables that are passed into a container. For example, a container may use an environment variable to set the database endpoint. Environment variable overrides let you set this information when the container is started with ‘run-task’. Now, you can set a different database endpoint for a test environment and a production environment by overriding the environment variable in the task definition when you run a task. Learn more about the feature here.

AWS CloudFormation Support
You can now use AWS CloudFormation to provision Amazon ECS clusters, register Task Definitions, and schedule containers. Read our documentation to learn more and use our sample template to get started.