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Is it possible to run mapped tasks in parallel using docker agent?

Hi Barry! Yes - the ability to parallelize tasks within a flow is independent of the type of agent you are running.  This behavior (at the flow-level) is configured through an execution environment — right now to achieve parallelism in Prefect requires running your flows on Dask: <https://docs.prefect.io/orchestration/execution/remote_dask_environment.html#overview>

<@UKNSNMUE6> I have tried to use Dask but it fails with error:
```[2020-05-19 18:40:04] CRITICAL - CloudHandler | Failed to write log with error: HTTPConnectionPool(host='host.docker.internal', port=4200): Max retries exceeded with url: /graphql/alpha (Caused by NewConnectionError('&lt;urllib3.connection.HTTPConnection object at 0x7fd68468d9d0&gt;: Failed to establish a new connection: [Errno -2] Name or service not known'))```
I have a local server, a local docker agent, and local dask scheduler with two workers. It works well without dask.

It appears your Docker container does not have access to your Server API

Yes, docker run with default bridge network which has no access to Server API. Is there any option to set a network for a flow?

Or default network with which dockers with flow are deployed by agent?

Yup for sure; you can start docker agents with
```prefect agent start docker --network "name"```

Hmmm… totaly have no idea why it does not have access to Server API, it is exposed on port 4200.