Frame forwarding with mac server

Given you're obfuscating, I can't be certain, but given the combination of obfuscation and problems, you're probably on a residential service tier and using some form of dynamic DNS. Public static DNS with public static IP connections generally don't have these issues.

The easiest way to do this is to set up public DNS to translate to your public static IP, port-forwarding at your gateway (and you probably want one of those) and it'll all work. The public DNS is preferably at your ISP, as (for the security-related services including https and SMTP) your ISP controls reverse DNS translations. This is the typical server-oriented connection.

Frame forwarding is a form of a reverse proxy scheme for web sites, and you likely don't want that.

Your public DNS should translate to your public static IP address, and not a redirect or frame-forward nor reverse proxy of any sort.

If you're using dynamic IP as I suspect here, then you're probably going to have all the usual issues that arise with network connectivity that result. Dynamic DNS works for simple stuff and is adequate for client-oriented activities, but it doesn't work particularly well with server-oriented network operations, and server-oriented traffic on residential ISP service tiers can be and variously is blocked by the ISP.

I set the primary dns name of my server to server.example.com en name of the server to 'server'

The big question is where are you doing this?

If you're doing this on your own server then it doesn't make much difference what you do - no one on the public internet is going to see it.

If you're doing this on a hosted DNS server (e.g. your ISP or domain registrar's DNS service) then that's wrong since the primary DNS server for your domain is your ISP/registrar.

Given that we don't know enough about your setup, it's almost impossible to advise the correct solution. Please describe your setup in more detail, specially as it relates to your DNS servers.

You would probably not be "forwarding" from your public DNS servers nor your public web sites nor from whatever it is that you're running here where you're setting up this "frame forwarding" stuff.

What little "forwarding" is involved here is usually implemented at the external gateway box on your network (within the firewall, gateway, router, NAT box at the edge of your network), by enabling and using a mechanism known as "port forwarding."

If you need or want to obfuscate your network settings, then I'd suggest getting somebody to look at this formally; somebody that can review the current configuration details and can interview you for your particular local requirements. These usually aren't difficult to sort out, and you'll get a chance to ask some questions.

If you're not going to follow that path, then here is how to setup network to access into your server. There are links there to other topics related to networking and DNS server configuration on Mac OS X Server.