If the WebSocket connection between your application and the DeepHub® closes unexpectedly, it is likely that: 
  • The proxy in front of the DeepHub® (the web server that hides the frontend and backend under one umbrella when Docker compose is used) is closing the connection after not seeing traffic for 60 seconds.
  • The client application is not sending a heartbeat ping. This can often be configured on the client side and prevents connection closure.


When this occurs, an error message will appear, such as "Unexpected status of SSLEngineResult after an unwrap() operation".

To resolve this issue, set a heartbeat ping on the client side. This is commonly referred to as "WebSocket ping pong" - here is an example of that.