Can I host both a TeamSpeak 2 and TeamSpeak 3 server on the same IP or physical machine?
Yes of course. The two products are independent of one another in terms of operation and licensing. However, please note that for non-profit entities the limitations are different. If you are a 100% non-profit entity you may host up to 10 virtual servers and 1000 slots using TeamSpeak 2, or 10 virtual servers and 512 slots using TeamSpeak 3 (which requires registration for a Non-Profit License (NPL)).