Subject: DHCP Server Question From: rareith@aol.comnospam (Bob Reith) Date: 5/7/01 8:20 PM Eastern Daylight Time Message-id: On my domain I am using NT4 with a PDC and BDC running DHCP and WINS. Since last summer when some work was done, I could see the DHCP service on the BDC server from the PDC and vice versa. In the last 2 weeks or so I am UNable to see DHCP service on the BDC from the PDC, but CAN still see the DHCP service on the PDC from the BDC. The error message when I try to connect from the PDC tells me that the BDC is down or the DHCP service isn't started, neither of which is true. And I can ping the BDC and the PDC from each other. Any ideas on what might have happened, and how to correct it? All that has been introduced to the environment is an additional switch. Posts and e-mail replies welcome. Thank you. Bob

Are you running DHCP server on both your PDC and BDC? If so, I hope you have different scopes configured on both. Otherwise, the same ip address may get assigned to your clients, and cause alot of problems on your network. Unless you have multiple subnets, and tons of clients, its not really worth it to have DHCP running on a BDC. It is, a "backup" domain controller after all.. I would just run DHCP server on the PDC & configure the BDC as the client. I bet that would solve alot of your addressing issues. choey

Yes, I'm running different scopes on each. What I don't understand is how I can see the PDC DHCP Server from the BDC, but not the BDC DHCP Server from the PDC. To apply your suggestion of running the BDC DHCP Service as a client -- two questions: 1. I've never thought of it that way -- what will that do for me since I'm not having address conflicts. 2. If I decide to do that, is it simply a matter of stopping the DHCP Server service and starting the DHCP Client service on the BDC? Thanks.

1. If you have a small network, (under 50 hosts) there is absolutely no need to have 2 DHCP servers. The BDC is there to take over login authentication & DHCP just in case the PDC goes down. Having both run the service just adds conflict and potential problems. 2. Yes, you could disable DHCP server service on the BDC, and enable it as a client. Then it will recieve an ip address from the PDC just like any other client. choey

Thank you for your reply and helpful information. Actually, there are 70-75 machines connected to this network. What I don't understand is why I can see the PDC DHCP Server from the BDC DHCP Server, but I CANNOT SEE the BDC DHCP Server from the PDC DHCP Server, something I could do up until a few weeks ago. Do you have any idea why something changed?

it could actually be WINS related; check net settings and WINS server.