Dhcp not updating in dns
Also make sure your DNS server are listed on the Name Servers tab. Ok so given that your DHCP server is not registering the records on behalf of the clients, and aside from your windows clients not being set to register with DNS on their NICs (which you should verify in TCP/IP properties on the client NIC), I would check the security settings on your reverse zone to make sure clients are allowed to register in the reverse zone.
This article covers the default security settings for DNS zones: the settings are jacked up (or even if they are fine), you might try just blowing away the reverse zone and recreating it since you basically have a non-functioning reverse zone as it is...
It can only register into a zone that exists on DNS and that zone updates have been configured to allow updates.
To overcome this, add the DHCP server (the DC) to the Dns Proxy Update group.
This will force DHCP to own all records it will create moving forward and will update an IP with a new name in DNS.
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