@Marvin While trying to submit flow run to ECS infrastructure from worker, I'm getting this error:

botocore.exceptions.ConnectionClosedError: Connection was closed before we received a valid response from endpoint URL: "<https://ecs.us-west-2.amazonaws.com/>".

and then prefect.flow-run.Crashed what could be the cause?

The error you're encountering,

botocore.exceptions.ConnectionClosedError

, when trying to submit a flow run to ECS infrastructure, suggests a network connectivity issue between your Prefect worker and AWS ECS endpoint. This can happen due to several reasons: 1. Network Configuration: Ensure that your network settings are correctly configured. This includes checking if your ECS cluster and Prefect worker have the necessary permissions and network access to communicate with each other. You might need to verify your security groups, VPC settings, and any internet gateways or NAT configurations. 2. AWS Permissions: Make sure that the IAM roles and permissions associated with your ECS tasks and Prefect worker are correctly set up. The following policies might be relevant: -

AmazonECS_FullAccess

-

AmazonEC2FullAccess

-

IAMFullAccess

-

AmazonEC2ContainerRegistryFullAccess

3. Endpoint Accessibility: Check if the ECS endpoint

<https://ecs.us-west-2.amazonaws.com/>

is accessible from your network. There might be firewall rules or proxy settings that are blocking access. 4. AWS Region Configuration: Ensure that the region configuration is correct in your AWS settings, as mismatched regions can lead to endpoint connection issues. 5. Temporary Network Glitches: Sometimes, transient network issues can cause such errors. It might be worth retrying after some time. For more detailed guidance on setting up ECS infrastructure with Prefect, you can refer to the Prefect 3.x documentation on serverless infrastructure. If the problem persists, you might want to check AWS CloudTrail logs for any denied requests or errors that could provide more insights.