I have a central office with a domain controller with DNS installed. Any computers at that office are on the same subnet (10.1.32.x) update their DNS entries correctly. DHCP is handled in that office by the DC
There are also two remote offices that connect over site-to-site VPNs. All the machines at the two remote sites are joined to the domain and are using the domain controller for their DNS. However, those remote machines are not registering their DNS entries with the domain controller. DHCP at each of these sites is handled by their respective firewall/router (Juniper SSG5 configured as a DHCP Server at each site).
The two remote sites have subnets (192.168.1.x and 192.168.201.x) that have been added as Sites on the Domain Controller, but the remote machines are still not registering in DNS.
Domain authentication is working properly remotely, GPO is being applied remotely.
How do I get client machines at each site to update their DNS entries? The check box for self-registering the connections DNS address is checked, but it isn't updating with the DC's DNS entries. DHCP is handled by an on-site Juniper SSG5 which does not send DNS updates back to the DC/DNS server.