I've published a stream service in GeoEvent 10.6 using the default data store / ArcGIS Server running on the same machine. The service is created as expected, but I'm not able to subscribe to it. I've tried to subscribe through a web map in ArcGIS Online, but also using the rest endpoint (http://<servername>/arcgis/rest/services/<service name>/StreamServer/subscribe). The error message I get using the dev tool of Chrome is
"Error during WebSocket handshake: Unexpected response code: 500.
I've recently federated the server to portal and I suspect that might be the problem as it used to work when the server was operating independently. However, I'm not able to find out why.