RE: VPN and server.app...
I'm trying to access it from a remote location. Is there any way I can set up a DNS (Dyn IP at my remote location) and somehow "allow" access to the server?
Hi,
I use DynDNS for what I believe is precisely what you are trying to do.
Now dyn.com recently did away (sort of) with their free dynamic dns service, but a form of it is still available. You first must sign up for their Dyn Pro Trial (free for 14 days) service, and then cancel it within the first 14 days. When you cancel it you get to keep a single hostname for free (unless they stopped this too).
So what does dyndns provide? Say your ISP switches your IP address from time to time, then the hostname you have from dyndns will be updated to still point to your machine at its new IP address.
Assuming that you open the correct tunnel for VPN L2TP through your router (you forward UDP ports 500,1701,4500 to the LAN IP address of your Mac OS X server), and you turn off your iCloud "Back to My Mac", which conflicts with the VPN service on port 4500, then you will be able to VPN from anywhere on the Internet to your Mac OS X server. Your home server's VPN service assigns your external computer (external meaning on the Internet) a local IP address, and as far as you are concerned your external computer is actually connected to your local (home) LAN. You can mount shared disks, print on your printers, screen share with the server, or connect your external computer's Server.app to the server at home (assuming that your external computer and the server at home are both running Mountain Lion with Mac OS X Server). Not only that, but VPN is capable of encrypting all traffic to and from your external computer to your home's LAN.
Good luck,
Switon
P.S. Of course, there are other ways of getting dynamic hostnames besides DynDNS. And, of course, if you know the IP address of your home machine you can just VPN in to its IP address without the need for an domain and host name. (I would try this first before going to the trouble of getting a dynamic hostname.)