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Greg_Vickers4
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Re: DNS duplicate record issue
LainRobertson I wont pretend to be familiar with the AD partition on the backend or the ldp.exe tool 🙂 However, when I do look at records in DNS Manager and each of these records are owned by themselves, I would think they would have to be separate records. See the below image which shows two DNS records for different clients, both have the same IP registered and their permissions show them to be the Owner of their DNS records. This is part of my confusion as the information in the below article clearly states DHCP must own the DNS records, which I've seen screenshots from other posts showing where the DNS record owner is listed as DHCPSERVER$ Overview to make this work: DHCP must own the record, not the client. This is done by configuring DHCP to register all DHCP clients, whether the client supports Dynamic Updates or not. As long as DHCP owns the record, can keep the records in the FLZ and RLZ up to date when the client renews its lease, same IP or different IP. Otherwise you’ll see duplicate A and PTR records in DNS, whether scavenging is enabled or not. https://blogs.msmvps.com/acefekay/2009/08/20/dhcp-dynamic-dns-updates-scavenging-static-entries-amp-timestamps-and-the-dnsproxyupdate-group/ Also - all of these clients are domain-joined and we do not have any RODC in our environment.21KViews0likes1CommentRe: DNS duplicate record issue
Dave Patrick Credentials for secure DNS updates is configured DHCP server is part of the DnsUpdateProxy AD group DHCP server is 2008 R2 (to be upgraded soon) and DNS servers are 2016, so dynamic updates are supported The DNS forward lookup zone where the duplicate DNS issue is occurring does not have WINS enabled21KViews0likes1CommentDNS duplicate record issue
Currently we are seeing duplicate DNS records for multiple DNS zones. This is specific to our VPN IP scopes, as other scopes do not appear to have this problem. In an effort to correct this issue, as it appears to be occurring from DHCP not being able to update/delete DNS records due to the client being the owner of the record, the below steps have been implemented. This is a smaller environment with approx 1200 endpoints, so the slightly more aggressive DNS intervals is not a concern. DHCP lease time adjusted to 8 days from previously 1 day DNS scavenging adjusted to "No Refresh + Refresh" = DHCP lease - 1 day 3 days (no-refresh) + 4 days (refresh) and 1 day scavenging https://docs.microsoft.com/en-us/archive/blogs/askpfe/how-dns-scavenging-and-the-dhcp-lease-duration-relate I also implemented Dynamic DNS Updates per the below MVP blog, but oddly the owner of all DNS records changed from SYSTEM as the owner to being self owned, rather than being owned by the DHCP server. https://blogs.msmvps.com/acefekay/2009/08/20/dhcp-dynamic-dns-updates-scavenging-static-entries-amp-timestamps-and-the-dnsproxyupdate-group/ The DNS duplicate issue is still occurring, which I'm assuming is due to the DHCP server not owning the DNS records and deleting them when their lease expires or updating when the IP is reassigned. Searched around quite a bit on this one and I'm stumped at this point. Anyone have an thoughts/suggestions to get DNS records to be properly owned by the DHCP server?22KViews0likes6Comments
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