I'm trying to set up a Windows domain in virtual machines (VMs) instead inside of an OpenStack deployment. I've configured one of the VMs to be the domain controller (including DNS server), running Windows 2012 server. I'm trying to figure out how to configure things so that the DNS server gets updated entries as new Windows VMs come up and join the domain.
From my understanding, the way this typically works is that the domain controller acts as both a DNS server and a DHCP server. When a new machine comes up and requests an IP via DHCP, as part of this process the DHCP client requests a DNS dynamic update which is handled by the DHCP server (James Hebden provided a link to this in the comment).
However, since these are virtual machines running inside of an OpenStack deployment, dnsmasq is acting as the DHCP server. I think this is the reason that the DNS server on the domain controller isn't updated with new entries, even when these instances are joined to the domain.
Is there any way to configure dnsmasq and/or the domain controller such that the DNS server gets automatically updated with the new instances? Or is that simply not possible unless I use the domain controller as the DHCP server?
If possible, I'd prefer to keep the DHCP server managed by OpenStack (i.e. dnsmasq), since I need OpenStack to manage the IPs for some desired functionality (floating IPs).