I've got two Windows 2008 Enterprise R2 servers both running DNS and DHCP called cod & lobster. DHCP is setup using the split scope option introduced with 2008 R2, whereby both servers should respond with the first response providing the lease. Setup is as follows:
- IP: 192.168.0.231
- Pool: 192.168.0.101 - 192.168.0.179, exclusion for 160-179.
- Response Delay: 0ms
- Authorised in Active Directory (Re-authorised to confirm) - Windows firewall disabled while testing
- IP: 192.168.0.232
- Pool: 192.168.0.101 - 192.168.0.179, exclusion for 101-159.
- Response Delay: 1000ms
- Authorised in Active Directory
All DHCP leases to clients are currently being issues by Lobster rather than Cod. Packet captures with Wireshark show the following (all to broadcast address):
Client - DHCP Discover
Lobster - DHCP Offer (after 1s delay) Client - DHCP Request Lobster - DHCP Ack Client - DHCP Inform
From my setup with two servers I'd expect to see a DHCP Offer coming from Cod almost immediately after the DHCP Discover.
Does anybody have any idea what would prevent the DHCP Server responding to the discover?