I have my local internal subnet of 172.16.0.255, which is what my router will assign physical machines on my network an address from. I have setup another subnet for my OpenStack instances, here:

gnychis@src-server1:~$ nova network-list
+--------------------------------------+---------------+---------------+
| ID                                   | Label         | Cidr          |
+--------------------------------------+---------------+---------------+
| fb655e7d-7824-4134-b0dc-e105a50e9326 | soroco-os-net | 172.16.2.0/24 |
+--------------------------------------+---------------+---------------+

When I create a Windows 8.1 instance, it properly gets an IP from that subnet:

However, when I create a Windows 7 instance, it seems to take on an IP from an incorrect subnet:

I'm not sure exactly how this happens. In fact, it knows of my WINS server (that I don't think I told it about) at 172.16.0.10, almost as if it's getting a DHCP response from my router rather than being assigned through OpenStack.

My instances shows a completely different IP for it, also (a proper one!):

Anyone know how to even begin debugging this? I am using nova-network, not neutron yet. Could it have learned about these IP settings when I created the image using virt-install and KVM? I can't seem to get it to forget them, even after a reboot.