How to set up redirection in WinServer to another server on the local network by accessing a subdomain?

Question

Computer networks

There is a server on WinServer2008. It has two network ones - one to the local network and the other to the provider's network.
PPPoE connection, dedicated IP.
On the server Routing - NAT is lifted.
There is a domain domen.ru, a site on a hosting. A subdomain is configured there for our dedicated IP (we go to subdomen.domen.ru - we get to our server, there is Apache and other little things).
There is one more server in the local network (on ubuntu, BigBlueButton is configured). It is necessary to make it so that when referring to the 4th level domain (for example, bbb.subdomen.domen.ru) from the Internet, go to this local server (to all ports, etc.).

Answer 1

If there is only one white address on the network card, then this problem can only be solved using http proxying - either using nginx or on the same apache.
httpd.apache.org/docs/2.2/mod/mod_proxy.html
Otherwise - raise the second IP to it, hang rules on it, forward traffic, register a new correspondence in DNS.