Perferct Server Howto, ISPconfig, internal/external DNS

My question is about general setup of this system.
I want to setup websites for myself and others.

Here is what I have:

Internal: XYZ.loc
subnet=10.0.1.0/24
Internal DNS server=10.0.1.1


External: XYZ.???? (My question is about a .com vs .priv)
DMZ network 192.168.0.0/24
Perfect Server ubuntu w/ISPConfig3 192.168.0.1
Sip server 192.168.0.2


Do I name my "perfect server" and other servers in the DMZ with .com or a non-private like .priv?
Do i create a dns zone for the "perfect server" and other servers in the DMZ in ISPCONFIG with the same .com or .priv domain?
What should I use to manage the servers in the DMZ?

obviously I am new to this!

Thanks

 

I suggest you use a real domain and create a hostname that points to your server's public IP.