How do you manage multiple (nearly identical) ECS Task Definitions?

Question

I have a Rails application in ECS and I've ended up with several Task Definitions. I have one TD for backup tasks, one for a Delayed Job service, one for nightly processing, etc. The problem is that each time I update my container image I have to also update each of these Task Definitions.

What am I doing wrong? Is there a better way to do this? Can I update the container image somewhere and just have all the tasks use that image?

What am I doing wrong?  Is there a better way to do this?  Can I update the container image somewhere and just have all the tasks use that image?

Giovanni Lauria · Answer

Create separate task definitions for each distinct purpose - one for your Rails application, one for backups/jobs, etc. This allows you to scale each independently.

Use environment variables or a configuration file to store common configuration that is shared across tasks, like database credentials. Then each task definition only specifies what is unique for that purpose.

Consider using a sidecar container pattern - have your tasks pull a common "sidecar" container image that runs scripts/jobs via environment variables or configuration passed to the task. This avoids duplicating the application image.

For communication between tasks, use AWS services like SQS queues or SNS topics rather than trying to connect containers directly. The sidecar container could listen to SQS and trigger scripts as needed.

Automate task definition updates using a tool like the AWS Copilot CLI. It can manage common configuration and make updates/rollouts easier across multiple definitions.

Refer to the AWS documentation on best practices for structuring task definitions and service configurations for guidance on common patterns and approaches.

How do you manage multiple (nearly identical) ECS Task Definitions?

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