Just to be sure, they are static IP entries...not getting them from dhcp which could be registering them for you.....
From: listsad...@lists.myitforum.com [mailto:listsad...@lists.myitforum.com] On Behalf Of Melvin Backus Sent: Tuesday, July 11, 2017 10:41 AM To: ntsysadm@lists.myitforum.com Subject: [NTSysADM] RE: Odd DSN behavior The conditional forwarding for the internal domain does point to internal servers. That hasn't changed however and has been the case for ages. All interfaces have the register connection checkbox cleared. That was checked initially but it was the first thing I looked at once I got involved. We unchecked that and were still having the issue. Any clue how a DDNS request would create a static entry? I didn't think that was possible. -- There are 10 kinds of people in the world... those who understand binary and those who don't. From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Michael B. Smith Sent: Tuesday, July 11, 2017 10:19 AM To: ntsysadm@lists.myitforum.com<mailto:ntsysadm@lists.myitforum.com> Subject: [NTSysADM] RE: Odd DSN behavior Just curious... are the forwarder/conditional-forwarder/root-hints of your DNS servers still configured the way you think? For each interface did you uncheck "register this connection in DNS"? From: listsad...@lists.myitforum.com<mailto:listsad...@lists.myitforum.com> [mailto:listsad...@lists.myitforum.com] On Behalf Of Melvin Backus Sent: Tuesday, July 11, 2017 9:40 AM To: ntsysadm@lists.myitforum.com<mailto:ntsysadm@lists.myitforum.com> Subject: [NTSysADM] Odd DSN behavior We've run across a very strange DNS situation that we can't explain. We have suspicions and a temporary fix but I'm hoping someone on the list has seen it already and give us some pointers. Recently stood up 2 new Skype for Business servers to replace the existing Lync 2010 servers. One internal and one edge server in each case. We've successfully migrated the topology and everything is running of the new servers. But now for the weird part. Every day, the internal DNS entry for the edge server gets changed. The static IPv4 entry for the internal interface (LAN facing) gets removed and there are new entries for the external interface IPs (public facing), both IPv4 and IPv6. The weird part is that the new entries are static as well, no timestamps. After much digging and churning we finally disabled the DNS Client service on that server and it didn't happen last night, but I'm trying to figure out how it was happening even with the DNS Client running. DNS on that box points to a DNS server on the public side, not the internal servers. DDNS updates should create a dynamic / timestamped entry. I've never seen a static entry created any way other than via manual intervention. Any one care to solve the puzzle? -------------------- Service Desk | 404-497-1599 | https://servicedesk.byers.com<https://servicedesk.byers.com/> Melvin Backus | Sr. Systems Engineer | Byers Engineering Company | 404.497.1565 -- There are 10 kinds of people in the world... those who understand binary and those who don't.
