I've seen several of the same question but so far haven't found a fix...
Two AD sites, both have 2 Domain Controllers, which also run DNS and DHCP.
Site 1 gives out DHCP addresses and updates the DNS, both A and PTR. The ACL on the records show the server in the list, indicating it created them.
Site 2 gives out DHCP addresses but updates in DNS are not working. The ACL on the A records show the client in the list, indicating it created it, but the PTR record is missing. It looks like DHCP isn't updating DNS, telling the client to do it, and I read that Windows 7 won't update PTR by default.
The forward lookup is the same for both sites (ad.fqdn) and the reverse is different for the two different ranges but are setup correctly.
All settings for DHCP and DNS are the same for both sites. I tried telling DHCP to update DNS regardless of the client request but no change.
XP / Older clients update fine, presumably because they still update PTR.
I haven't tried credentials and the DNSUpdateProxy group as I don't believe they are required (on DCs) and also the other site is working fine without these.
Running ipconfig /release does remove the entry from DNS correctly, and manually removing the DNS entry and renewing adds it back in again (did this to prove it wasn't because it was owned by something else)
Any suggestions please?