I see (on https://github.com/allegroai/trains/issues/126 ) that you got result code 400 from port 8008. This makes sense (when not sending anything to the server) it just tells you that it didn't get anything meaningful.

You should be able to get the same result if the proxy is configured correctly (and you send nothing in the message body).
And if the connection still times out, I would try using the proxy with a browser to 8008, and checking if you can get to the server at all using that proxy...

after trying different options mentioned in FAQ I got the following error

Also which option did you try that changed the response?

What exactly produced this response? cURL?

Just updating, this issue is being discussed here: https://github.com/allegroai/trains/issues/126

Then I did set CURL_CA_BUNDLE to empty string

First I set no_proxy to 127.0.0.1

Hi Manish, did you check our FAQ?

https://allegro.ai/docs/faq/faq/

Exception: Failed getting token (error 401 from http://dataanalytics2:8008 ): Authorization Required
Error: could not verify credentials: