Vaadin 8 + SpringBoot fails when deployed on a server (serverPrivate) behin

The scenario is a Vaadin 8+ SpringBoot application hosted on a server with a private IP address (privateServer/path2Vaadin).
There is a proxy server with public IP ( that has a rule to forward requests with sufix /path2Vaadin: → forwarded to http://privateServer/path2Vaadin/

All the request from client side are generated correctly except the ones involving the vaadinServlet (eg. the related with the heartbeat)


A good request generated (most of the client requests are correctly generated):

Bad request (client tries to reach this url: view that path2Vaadin has been stripped out):

How could I tell Vaadin or Spring to append path2Vaadin/ only to requests involving the vaadinServlet/ path?

This is quite frequently asked. What you need to do depends on how to configure your proxy.

Check this one: