I have been assigned to support a 50-user company currently running a workgroup. We have a cisco 2800 router connecting to our ISP. Connected between our internal network and the 2800 router is an ASA 5505 firewall. The firewall is issuing DHCP and I am not sure if it is providing DNS or if the ISP is providing DNS services (Any way to tell on this?). Anyway I promoted a standalone Windows 2003 SP2 server to a domain controller. This was an extra machine and there are no other domain controllers on the network. I implemented DNS on it and configured the DNS forwarding to point to the ISP's DNS servers. I tested a client machine and was able to join the domain no problem. But when I log into the domain, it takes over 10 minutes to log in! I'm pretty sure it's a dns issue but not sure where to begin. Any help asap would be appreciated. Maximum points assigned.
Oh, also, if do an IP CONFIG /ALL on the client machine the ISP DNS servers show up. I thought that the Domain Controller's address should show up since that is doing the forwarding. Is there some DNS setting in the ASA 5505 that may be overriding my Domain Controller's DNS? I don't know. Just thinking out loud.