Thanks for your reply. My comment is as follows:-
1) It is enterprise license. (Attached for your reference.)
2) Yes, I have added the server by IP Address not by host name and which DNS you are talking about. Could you please explain a bit more. All servers can able to ping by there IP Address.
(Moderator Note: a.p removed screen shot with license keys!)
Thanks & Regards,
Gaurav Asthana