Hey folks, we’re experiencing some intermittent issue with Fargate Agent in EC2 mode. we are on

prefect==0.13.13

From time to time, tasks fail to start and we get the following error:

f6edaa77-6dc6-4b85-953a-25ccdb4fb366 finished in state <Failed: "list index out of range">

where

f6edaa77-6dc6-4b85-953a-25ccdb4fb366

is the task run id. We can’t find any meaningful log on ECS, but I suspect this error is caused by the fact that the container fails to start. Any suggestions? Thanks!

Hi @ale, this only happens sometimes? Is it always the same task?

It is happening randomly to several flows (which are ecs tasks in our case)

And nothing in the Flow gets run at all right?

Exactly

Ok I’ll ask the team and get back to you

Thanks @kevin! 🙌

Do you see anything on the CloudWatch logs side?

The only logs I see are related to Prefect Agent, but nothing related to ECS service. I was looking for some ECS logs for tasks that failed to start...but I found nothing 😭

Man sorry there aren’t any clear suggestions other than to upgrade because that agent is deprecated