I’ve got a decent grasp on DNS, but have a situation I’m a little confused on currently.
I’m working on an office network consisting of a Windows 2000 domain controller, Windows 2003/Exchange 2003 mail server, and several workstations. Our firewall is a SonicWall.
The company’s websites are all hosted off-site by a company that handles all related DNS. We’re about to switch hosting companies for our off-site websites, thus IP addresses will be changing. I’ve got the DNS ready to go with the new hosting company, but it’s the in-office set-up that I’m worried about. See, on the in-office domain controller there are Forward Lookup Zones created for some, not all, of the domains that are hosted off-site. That being said, any DNS changes done to those domains off-site, have to be duplicated here in the office.
My question is this… are these Forward Lookup Zones even necessary? They don’t exist for all the domains hosted off-site by the company, and they don’t exist for all of the domains we handle mail for here in the office. Each workstation in the office is set to use the domain controller as it’s sole DNS server, and the SonicWall firewall is set up to use DHCP, with it’s DNS servers as 1) the domain controller again, and 2, 3) our ISP’s DNS servers. Correct me if I’m wrong, please, but with workstations being set to look at the domain controller ONLY for DNS, I’m assuming it still rolls over to the DNS set up in the SonicWall (the domain controller again, then two of our ISP’s DNS servers) for any requests not filled by the domain controller? Thus, if I deleted these Forward Lookup Zones in-office, requests for those websites should, like all others, go out to our ISP’s DNS servers? No?