ASG capacity providers are currently immutable objects. With this proposed change, we will add the ability to change the managed scaling, target capacity, and managed termination protection settings on an ASG capacity provider.
Excellent!
Whoever created the error message for duplicate capacity provider thought this was already possible; I am glad they will eventually be made right:
The specified capacity provider already exists. To change the configuration of an existing capacity provider, update the capacity provider.
Thanks for pointing this out, we will change the error message until such time that the update API is launched.
Error message is still there @coultn

Very excited for this functionality! Given the complicated formula that CP's use to determine the desired count, having the ability to tweak this to find the proper level for the workload will greatly improve the usability of this tool.
I would like to add to this the ability to change some of the policy settings for managed scaling as well? In my case im after the instance warm up. The ECS optimized image take a lot less than 5 minutes to start up and it would mean i could scale significantly faster.
Yes, please. Need to be able to change the Warm up time (300 seconds is a lot). IS there any way to change it using the Cli ?
Any updates on this?
Delighted to know this is WIP. It would be very welcomed to be able to change the target number of the capacity provider in a prod environment. It's my most frustrating encounter in AWS to date, everything usually is so flexible and awesome. Look forward to capacity providers keeping that high standard.
UpdateCapacityProvider API is now available:
https://aws.amazon.com/about-aws/whats-new/2020/11/amazon-ecs-capacity-providers-now-support-update-functionality/
Also, both the CreateCapacityProvider and UpdateCapacityProvider APIs support specifying a customer instance warm-up time:
https://aws.amazon.com/about-aws/whats-new/2020/11/amazon-ecs-cluster-auto-scaling-now-supports-specifying-a-custom-instance-warm-up-time/
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Error message is still there @coultn