Can I use a 7.0.0 client against a 5.6 server (new against old), or a 6.0 client against a 7.2 server (old against new)? No, this is not recommended. No compatibility assurances are given between ...
Description of the problem including expected versus actual behavior: Connecting to elasticsearch woth the .net client fails where the same request in a web browser and with CURL succeeds.