Just woke up to find all our ECS Worker tasks failing as the

task_definition_arn

we have set as override in the deployments aren't being respected anymore. Turns out the default

command

we have used from the prefect-aws guide

pip install prefect-aws && prefect worker start

has started to install

prefect-aws==0.5.0

which is now installing Prefect 3 and that's not respecting

task_definition_arn

value and generates its own task definition. To start with there is the incompatibility in Prefect 2 in the server and Prefect 3 in the ECS Worker and ignoring the task_arn seems to be an undocumented regression. The solution is to change the worker command in its task definition to:

pip install prefect-aws==0.4.19 && prefect worker start

hi @Arun yes! the default installs for both

prefect

and its integrations are prefect 3.x versions now if you simply install extras like

prefect[aws]<3

you will always get the right version of the package i would also recommend not installing deps at runtime and building static images up front

The ECS worker doesn't do anything other than to schedule ECS tasks, so, we were just following the prefrect-aws docs and installing it in runtime. We still are 😛

@Arun Can you share your base job template that respects

task_definition_arn

and runs flows successfully? I can get the worker (w/

prefect-aws==0.4.19

installed) to start ECS tasks using the provided

task_definition_arn

, but it doesn't supply a

command

to

ecs:StartTask

, which I gather needs to be

python -m prefect.engine [task-run-id]

.