Virtualbox, how to organize simultaneous visibility of 2 sites from the outside?

Question

virtual box

For the first time faced with virtualization.
Given:
1) Host system: Dedicated server (static ip, visible from the Internet), ubuntu 12.04, nginx (frontend) + apache, virtualbox 4.3\phpvirtualbox.
2) 2 identical guest systems: Centos 6.5, nginx (frontend) + apache. Each posted on the site.
Can you please tell me how to make these two sites simultaneously accessible from the Internet? domains are delegated to the ip of the host server. Is there any way to tell the host web server to forward requests to the guest? As I understand it, if there was one site, it would be possible to forward the 80th port, but there are, in fact, two sites.

Answer 1

buy another IP or set up an nginx proxy on the host

Answer 2

it is enough to configure nginx on the host