I think the IP assigned by my router should be static.
That makes no sense. If an address is assigned by the router to another device then its not static. To give a computer a static address, you need to edit the operating system's network configuration and assign it a static IP address.
So when I turn off the router's DHCP and enable the DHCP Server in
Windows, do all my computers (I have 3) automatically receive their IP
from the server? How does that work?
Yes. DHCP, on a simple network works using the DORA principle.
- Discovery - the client broadcasts a message on the local network segment its connected to, to discover available DHCP servers.
- Offer - a suitably configured DHCP server receives a request from a client, and offers it an address from its pool of available addresses.
- Request - The client replies to the offer, requesting the address received in the Offer.
- Acknowledgement - The server acknowledges the request, marking the address as used in its pool of addresses, and informs the client of how long the address lease is valid for, and any other information needed.
As such, any device on a network segment can be a DHCP server, it doesn't have to be the router or any other "special" device on the network. When the devices on your network reach the end of their leases (or you reboot them, which will force them to check their lease is still valid) they will simply broadcast a request for a DHCP server and will find the new server instead of the old, inactive one.
The domain for the AD should be 'home.internal'.
Ok. If you're trying to learn AD then that's not a "best practice" address, but fair enough.
I also have IIS running that needs to be accessible from within and the internet. I don't think that has anythign to do with it?
Not as such. Though if you're promoting the server running IIS to be your domain controller, this may well change your IIS configuration (As "local" accounts aren't available on a domain controller, the accounts used by IIS and any web applications you're running will change).
Also, with wireless clients, how would they get their IP automatically if the DHCP in the router is turned off? They won't, right?
Yes, they will, unless your wireless router is configured in a very odd way. The wired and wireless networks typically appear as one network to the devices on that network.
I also have not understood why I need the DNS server.
DNS is a central component of Active Directory. See this: How DNS Support for Active Directory Works