I notice that your Docker Compose configuration is incomplete, and there might be a few issues to address. Let me help you set this up correctly. 1. First, your current configuration is missing some crucial environment variables. Here's an improved version of your `docker-compose.yml`:

yaml
services:
  prefect-ui:
    image: prefecthq/prefect:3.2.6-python3.11-conda
    command: prefect server start --host 0.0.0.0 --port 4200
    ports:
      - "4200:4200"
    env_file:
      - .env
    environment:
      PREFECT_UI_PORT: 4200
      PREFECT_UI_HOST: 0.0.0.0
      PREFECT_SERVER_API_HOST: 0.0.0.0
      PREFECT_API_URL: <http://0.0.0.0:4200/api>

2. In your

.env

file (which you started to mention but didn't complete), you should include:

PREFECT_UI_API_URL=http://<your-vm-ip>:4200/api
PREFECT_UI_URL=http://<your-vm-ip>:4200

Replace

<your-vm-ip>

with the actual IP address of your VM that's accessible from outside. 3. Common issues to check: - Make sure your VM's firewall allows incoming traffic on port 4200 - Verify that the VM's security group (if using cloud infrastructure) allows inbound traffic on port 4200 - Ensure your VM's network interface is configured to accept external connections 4. To test the configuration: - Inside the VM:

curl <http://localhost:4200/api/health>

- Outside the VM:

curl http://<your-vm-ip>:4200/api/health

5. For clients connecting from outside the VM, they should configure their Prefect client with:

bash
prefect config set PREFECT_API_URL="http://<your-vm-ip>:4200/api"

Let me know: 1. Are you able to access the UI at all (even with errors)? 2. What specific error message do you see when trying to access the UI? 3. Can you confirm if port 4200 is accessible from outside the VM (using curl or telnet)? This will help me provide more specific guidance for your situation. Also, while version 3.2.6 is functional, you might want to consider upgrading to the latest 3.x version for better stability and features. The current setup approach remains the same across 3.x versions.