Why are there so few A-records in my DNS server?

Question

Domain Name System

OS: Windows Server 2012
Why do I have about 200 entries in the DHCP server (renting an IP address for 3 days), but only 120 in the DNS server?
The DNS is cleaned every day so that there are fewer conflicting records with duplicate IP addresses. Blocking interval (no-refresh) - 2 days, refresh interval (refresh) - 2 days.
On DHCP dynamic update is enabled, name protection is enabled.
If it's scavenging that removes the A-records, how can this be avoided? As I understand it, it should not delete them until the no-refresh and refresh intervals have both expired. If I'm wrong, please tell me the working scheme for intervals and cleaning.
Those. For some computers, the DNS server cannot resolve IP addresses - this is the problem.

Answer 1

Set to clean dns once a week for example. It is also possible that you have some intervals configured for the server, and others for a specific zone.
You can smoke man:
https://technet.microsoft.com/en-us/library/cc7716...

Answer 2