Do you only need 1 copy ?

Hello Everyone
this may be a stupid question as i dont normaly use a server but in writeing this about my college all the computers are run by one big server and i was wondering if you buy 1 copy of unity pro can you then install that to the server and accsess it all accross all the computers or would 1 lisence be able to activeate more than 1 pc ???

One license can activate two computers. You have to own both of them, however.