Hi, This is our setup We have 3 DNS servers, 2 DHCP servers and 1 domain. We have DNS dynamic updates registration credentials setup. Enable DNS Dynamic Updates is enabled. Always dynamically update DNS A and PTR records are selected. Discard A and PTR records when lease is deleted. Dynamically update DNS A and PTR records for DHCP clients that do not request updates is checked. On Reverse Lookup Zones, 192.x.x.x subnet, we have aging/scavenging properties aging set to enabled, No-refresh interval 4 days, Refresh 5 days. Our scavenging setup is not deleting duplicate records in Revers Lookup Zones. Please help what is wrong with our setup?

Aging/Scavenging is enabled at the server object level & at the zone level. Take a look at this summary: Understanding DNS Aging and Scavenging http://www.anitkb.com/2010/04/understanding-dns-aging-and-scavenging.html Visit: anITKB.com, an IT Knowledge Base.

Thanks! When I enabled the server level I get this prompt: "Apply these settings to the existing Active Directory-Integrated zones" check box. Should I select this or not?

If you intention is to enable Aging/Scavenging on the zones, then yes. However, before you proceed with enabling these settings tonight, you should do some reading up on this topic. In addition, I would always recommend that you test out new settings in a lab/validation environment prior to implementing in production. Its always good with any implementation to take a structured approach with a back-out plan. Visit: anITKB.com, an IT Knowledge Base.