Just drop me a PM for now so that I would at least have your name in my contacts. I have finals this week, but hopefully, thereafter, I can dedicated a few solid weeks between my primary job and this project to come up with something. I haven't look at IIS 5.0 to see if the commands are different from IIS 6.0, so far now, the specs outlined above is going to be requirement. I haven't looked at what are all the available software free/commercial for DNS, so you'll going to need to know how to administer that on your own.
I think the two top MS DNS (?) and BIND. A buddy of mines which I worked with him together building a control panel for FreeBSD, we used PowerDNS which works great primarily because driven by a database backend. If you used BIND before on a UNIX server, you have to reload it. With PowerDNS, there's no need to reload as the comitted changes are instantly made. So I'm considering of supporting it because in most cases, the DNS server should reside on a second machine. Installing it should be relatively simple as you need just a ODBC database (Access, MySQL, etc.) then the CP can open a connection to it from a remote server.
I'm probably rambling on too much, but I definitely want to make this an initiative and progress in the coming weeks as another buddy at University of Texas is hopefully going to come through after his finals and setup a staging environment for VDS. We got a little hung up on the journaling file system that would be most suitable for FreeBSD's Jail.
As for VDS servers on Windows, the CP will be designed such that you can use software like VMWare (lots of overhead?) to split up a machine to offer VDS on that platform. Though I have to rethink the server roles as I've always dealt with Admin, Reseller, and Domain Owners. So now, it's like Admin (Master), Server Owner (Slave machines), Reseller, and Domain Owners.
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