Your windows 2003/2008 dhcp server will only listen on one ip per nic

Yes, there are known issues with Firewalls, DHCP Server not authorized  or Scope not activated or simply the broadcast not reaching the server.

A lesser known issue is that per NIC you can effectively only have one Scope and it must be a scope that contains the first IP address of the NIC.
Easy to verify the first IP address, it’s the one listed on top of the IP addresses in the IP Settings Tab.

Another good check is via the DHCP servers bindings:

If your scope does not contain any of these IP addresses and you are not using DHCP Relay Agents, it will never give out an offer for it.
I did not find an easier way to change the order of IP addresses then  re-add all of them.

You can do a quick test with portqry.exe (Windows Support Tools):
portqry -n -e 67 -p UDP

From the IP address example above:
First IP: 172.20.20.20

Attempting to resolve IP address to a name…
IP address resolved to REG-DC2.reg.intra
UDP port 67 (bootps service): LISTENING or FILTERED

Now the Additional IP: 172.80.80.20

Attempting to resolve IP address to a name…
IP address resolved to REG-DC2.reg.intra
UDP port 67 (bootps service): NOT LISTENING

You can see the DHCP server is not listing on this port and IP.
If I was to create only the scope 172.80.80.0/24 it would appear to me like my DHCP server was not working at all, I would be able to capture the traffic using
Wireshark/Netmon and see the DHCP Discover broadcast, but no offer from my Server.
If I now create the additional scope 172.20.20.0/24, all my clients would receive a lease from that scope and 172.80.80.0 would remain dead.

Tested on both Windows 2003 and 2008 but all the screenshot are from 2003.

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