Deregistering task definition revisions - Amazon Elastic Container Service

Deregistering task definition revisions

If you decide that you no longer need a specific task definition revision in Amazon ECS, you can deregister the task definition revision so that it no longer displays in your ListTaskDefinition API calls or in the console when you want to run a task or update a service.

When you deregister a task definition revision, it is immediately marked as INACTIVE. Existing tasks and services that reference an INACTIVE task definition revision continue to run without disruption. Existing services that reference an INACTIVE task definition revision can still scale up or down by modifying the service's desired count.

You can't use an INACTIVE task definition revision to run new tasks or create new services. You also can't update an existing service to reference an INACTIVE task definition revision (even though there may be up to a 10-minute window following deregistration where these restrictions have not yet taken effect).


At this time, INACTIVE task definition revisions remain discoverable in your account indefinitely. However, this behavior is subject to change in the future. Therefore, you should not rely on INACTIVE task definition revisions persisting beyond the lifecycle of any associated tasks and services.

Use the following procedure to deregister a task definition revision.

To deregister a task definition revision

  1. Open the Amazon ECS console at

  2. From the navigation bar, choose the region that contains your task definition.

  3. In the navigation pane, choose task definitions.

  4. On the task definitions page, choose the task definition family that contains one or more revisions that you want to deregister.

  5. On the task definition Name page, select the box to the left of each task definition revision you want to deregister.

  6. Choose Actions, Deregister.

  7. Verify the information in the Deregister task definition window, and choose Deregister to finish.