< Marvin> I deploy prefect with docker compose Prefect serve Prefect Community #marvin-ai

@Marvin I deploy prefect with docker compose. Prefect server and Docker worker in separate container, when running flow, new container with run cannot connect to server container. How can I fix that?

Marvin

03/14/2025, 9:23 AM

To resolve the issue of your Docker worker not connecting to the Prefect server, you should ensure that both containers are on the same Docker network. Here are some steps and considerations: 1. Docker Network Configuration: Ensure that both the server and worker containers are in the same network. You can define a custom network in your

docker-compose.yml

file:

Copy code

yaml
   networks:
     my-prefect-network:
       driver: bridge

   services:
     server:
       image: prefecthq/prefect:latest
       networks:
         - my-prefect-network

     worker:
       image: prefecthq/prefect:latest
       networks:
         - my-prefect-network

2. Service Discovery: Use the service name to connect to the Prefect server from the worker. For example, if your server service is named

server

, you can connect to it using

<http://server:4200>

(or whatever port the server is listening on). 3. Environment Variables: Ensure the worker knows where to find the server by setting the appropriate environment variables. For example:

Copy code

yaml
   environment:
     - PREFECT_API_URL=<http://server:4200>

4. Check Docker Logs: Use

docker logs <container_id>

to check for any specific errors or issues in the logs of both the server and worker containers. 5. Port Exposure: Ensure that the Prefect server is exposing the necessary ports and that they are correctly mapped in

docker-compose.yml

. You can find further guidance and examples in the Prefect documentation on Docker deployments. If the issue persists, consider checking for any network-related errors or misconfigurations in your Docker setup or refer to Prefect's GitHub issues for similar problems and their solutions.

Krystian

03/14/2025, 9:47 AM

@Marvin this is the error msg i got in created container for run

Copy code

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      |   File "/usr/local/lib/python3.12/site-packages/httpx/_client.py", line 1730, in _send_single_request
      |     response = await transport.handle_async_request(request)
      |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
      |   File "/usr/local/lib/python3.12/site-packages/httpx/_transports/default.py", line 393, in handle_async_request
      |     with map_httpcore_exceptions():
      |          ^^^^^^^^^^^^^^^^^^^^^^^^^
      |   File "/usr/local/lib/python3.12/contextlib.py", line 158, in __exit__
      |     self.gen.throw(value)
      |   File "/usr/local/lib/python3.12/site-packages/httpx/_transports/default.py", line 118, in map_httpcore_exceptions
      |     raise mapped_exc(message) from exc
      | httpx.ConnectError: All connection attempts failed
      +------------------------------------
An exception occurred.

Marvin

03/14/2025, 9:48 AM

Your message was too long by 2015 tokens...

Marvin

03/14/2025, 9:48 AM

Your message was too long by 196 tokens...

Marvin

03/14/2025, 9:49 AM

Your message was too long by 114 tokens...

Marvin

03/14/2025, 9:50 AM

The error message you're seeing,

httpx.ConnectError: All connection attempts failed

, indicates that the container running your flow cannot establish a connection to the Prefect server. Here are some steps to troubleshoot and resolve this issue: 1. Networking: Ensure that both the Prefect server and the worker containers are part of the same Docker network. This allows them to communicate with each other. You can specify a network in your

docker-compose.yml

file:

Copy code

yaml
   networks:
     my-prefect-network:
       driver: bridge

   services:
     server:
       image: prefecthq/prefect:latest
       networks:
         - my-prefect-network

     worker:
       image: prefecthq/prefect:latest
       networks:
         - my-prefect-network

2. Service Names: Use the service name to connect to the Prefect server from the worker. If your server service is named

server

, use

<http://server:4200>

as the API URL. 3. Environment Variables: Ensure the worker container has the correct environment variable set to locate the Prefect server:

Copy code

yaml
   environment:
     - PREFECT_API_URL=<http://server:4200>

4. Port Mapping: Verify that the Prefect server is exposing the necessary ports and that they are correctly mapped in the

docker-compose.yml

. 5. Check Docker Logs: Use

docker logs <container_id>

to see detailed logs from the server and worker containers for any additional errors. 6. Proxy Settings: If you're running in an environment that uses proxies, ensure that the necessary proxy environment variables are set, such as

HTTPS_PROXY

and

SSL_CERT_FILE

. For more detailed guidance, you can refer to the Prefect documentation on Docker deployments and check the GitHub issues for any similar problems and solutions.

Chinh Dinh Minh

03/16/2025, 4:01 AM

Can you provide more context?

11 Views

Open in Slack

Previous Next