Hello, I recently tried to move my current setup (Server + Worker) from EC2 to a fully self managed ECS cluster elaborating on a Terraform template provided here. The goal here is to hide the server behind a load balancer. However, I have a hard time figuring out how to configure the server so that the UI remain accessible. I pretty much tried all combinations of the following environments variables in my ECS task definition :

command = ["prefect", "server", "start", "--host", "0.0.0.0"]
      environment = [
        {
          name = "PREFECT_UI_API_URL",
          value = "http://${aws_lb.prefect_ecs_alb[0].dns_name}:4200/api"
          #value = "<http://0.0.0.0:4200/api>"
        },
        {
          name = "PREFECT_API_URL",
          value = "http://${aws_lb.prefect_ecs_alb[0].dns_name}:4200/api"
          #value = "<http://0.0.0.0:4200/api>"
        },
        {
          name = "PREFECT_SERVER_API_HOST",
          value = "${aws_lb.prefect_ecs_alb[0].dns_name}",
          #value = "0.0.0.0"
        },
        {
          name = "PREFECT_UI_URL",
          value = "http://${aws_lb.prefect_ecs_alb[0].dns_name}:4200"
          #value = "<http://0.0.0.0:4200>"
        }
      ],

I keep getting

Can't connect to server api

errors or a black screen. It seems I can reach the server from my local development machine though. Is there any ressource available for this kind of issue?