Can DNS be used in BDC and PDC?

Answer 1

There should be one DNS server in the Network - ideally not on the PDC - so BDC would be fine - or even a non Domain Controller.

Answer 2

Assuming that you're talking about a Windows NT network (not Active Directory) DNS isn't particularly necessary. Windows NT networks are not dependant upon DNS and the DNS service bundled with Windows NT Server does not dynamically update so you have to manually add A records for every host on the network.

It might have some value as a caching DNS server if you have a lot of hosts accessing the internet as it will minimize external DNS queries somewhat. It also may have some value as you prepare for an upgrade to Active Directory if you will have a DNS server at the same IP address after the upgrade.

Unless you have a very large network or are using very old hardware there's no reason why you can't install DNS on a Domain Controller, either the PDC or a BDC.

I've installed hundreds of Windows NT networks and only once used DNS on an NT network and that was on a huge corporate network with nearly 100 NT domains at over 200 sites.

Answer 3

DNS is a service. Yes, you can run that service on your PDC and or your BDC.

Unless you are short servers it is not a good idea. Domain controllers should do just that, control access / validate access to the domain, you don't want them doing everything under the sun unless you don't have the resources.