When should I create a new Primary DNS Zone?

Question

In an Active Directory domain with a single primary DNS zone and integrated DHCP, every DHCP client will register themselves with the server holding the primary DNS zone when their lease is renewed.

If there are a lot of clients, or if the WAN links are very slow, couldn't this cause problems? Would it ever be a good idea to create a new primary DNS zone in a different location? Alternately, what would be the reasons against creating a new DNS zone?

Answer 1

VERY few reasons to have more than one primary zone. Seriously. This is - in the context of AD - more a leftover. Well, not really...

• Multiple domains in one forest MAY have multipe top level domains, though it is technically not necessary.

But at the end, it is so because DNS supports it.

Answer 2

The DHCP clients will only register in the zone if configured to do so. You can turn that off.

If you have a local DNS and DHCP server in each location then only syncing those zones will go across the WAN. However, even with multiple zone, if they are ActiveDirectory integrated, they will still sync across the WAN, so no gain there. You can tune how often the sync takes place though.

The zone is created for a domain though, so you would have to create a whole new domain. You might be better off using sub-domains for this - uk.domain.com, us.domain.com. But, as I said above, if using ADI the data will still sync.

However, with local servers, the local PCs will see less latency when they request an IP and it gets added to DNS. That addition to DNS won't impact the client at all though, as it is distinct from the IP granting process.

Are you actually seeing an issue here or just generally looking to improve performance?

Answer 3

You wouldn't need to make another zone since the zone would replicate (as Alex indicated). Off the top of my head if you were to create a new primary zone, I think it is possible to have workstations with a different dns suffix to be members of a domain with a different dns suffix, but the act of joining the domain will create a new primary name for that computer in the AD zone. You would have to had previously manually created the DNS entry in the new zone.