I'm trying to figure out how one goes about setting up DNS in a setup like at my work. We have:
- A "business" DSL line that is just a home DSL line with a dedicated IP address
- A Sonicwall router (NAT/VPN) appliance connected to the DSL modem (192.168.1.1)
- A Windows Server 2008 R2 box running Active Directory and DNS (192.168.1.2)
Each PC on our network is configured to use 192.168.1.2 as DNS, using manually-configured IP addresses. DHCP is enabled on the Sonicwall for VPN clients, not used for our workstations.
The server's NIC is configured to use:
127.0.0.1 188.8.131.52 184.108.40.206
The second and third entries are our ISP's DNS servers.
The problem is that while everything works, DNS resolution is absurdly slow for internet sites. Using GRC's DNSBench.exe, uncached requests to 192.168.1.2 are taking 3849 ms! Connecting to our ISP's DNS servers directly takes about 100 ms for the same uncached requests.
Thanks for any help - I really don't know what I'm doing here. Hah.