dhcp service on W2k server

[jftuga]

Our network has 3 Active Directory DCs all running Windows 2000 Server. One of them runs the DHCP service and serves out IP addresses to 250 PCs. We do NOT have a cluster. A couple of weeks ago this server hung and wasn't restarted until the IT staff got to work the next morning at 8:00. However, there are some people who get to work at 7:30 and they could not get an IP address and therefore not log onto the network.

I know you can't really set up a "backup" DHCP server as the DHCP client (Windows XP and 2000 in this case) will send out a broadcast and use the IP address in the first valid DHCP reply that it receives.

My question is how can I set up a (redundant, backup, failover, secondary, stand-by, etc.) DHCP service on one of my other two DCs? Is this possible? Will having two servers send out IP addresses from identical ranges cause problems or conflicts?

One thing just occurred to me as I was typing in this message. If this it not possible, could I have one server use a range of 10.0.0.1 - 10.0.0.127 and the other server use a range of 10.0.0.128 - 10.0.0.254? I would configure them both to use the same netmask and broadcast addresses.

Thanks,

-John

Edited February 24, 2006 by jftuga

[nmX.Memnoch]

One thing just occurred to me as I was typing in this message. If this it not possible, could I have one server use a range of 10.0.0.1 - 10.0.0.127 and the other server use a range of 10.0.0.128 - 10.0.0.254? I would configure them both to use the same netmask and broadcast addresses.

This would work but since you have 250 PCs, half of your network would be without an address.

You shouldn't have two DHCP servers serving the same address range. One thing you can do is configure one DHCP server to serve 10.0.0.x addresses and the other to serve 10.0.1.x addresses. Then just configure the SM and GW appropriately so they can talk to each other.

Also, you're probably already doing this but be sure to set exemptions for your server IPs.

Edited February 24, 2006 by nmX.Memnoch

[jftuga]

Actually, those 250 PCs are split among several VLANs, so there is at most ~100 PCs per broadcast domain.

-John