Dns clients not updating records
In the case of using the DHCP service to register client's DNS records, you need to add the DHCP server's computer account to the DNSUpdate Proxy Security group and set the appropriate settings on the DHCP server's properties.
In this case, the DNS client registers the host (A) resource record.
During the Refresh interval, which is 7 days by default, the client's DNS time stamp is updated.
During the Scavenging interval, old DNS resource records are automatically deleted.
When the DNS client is configured to use a static IP address, the DNS client registers both host (A) resource records and pointer (PTR) resource records on the DNS server.