Univention Bugzilla – Bug 32427
Free DDNS Adresses after DHCP-Lease Expires
Last modified: 2020-07-03 20:51:58 CEST
The DDNS address should be released when the DHCP-Lease expires. This has been reported to be one of the two options in AD. It would also help, as it shows, which computers are currently are online. Ticket: #2013082821003261
First, I think we are talking about PTR records here. A/AAA records in contrast are created (and owned) by the Windows clients by default and the clients update them to their current IP. PTR records in contrast, are created by the DHCP server by default. Depending on the configuration, the client may also do it itself instead. * In case the DHCP server has created the record (Bug 39514), it may be possible to instruct it to remove it at lease expiry, see Bug 301 for ideas. In case there are two DHCP servers, there are ownership issues, see e.g. http://windowsitpro.com/windows-server/dns-update-credentials-vs-dnsupdateproxy . * In case the client registered it, he should clean it up, but usually he doesn't, see https://support.microsoft.com/en-us/kb/2933537 . * In reality, both approaches might leave stale PTR records, owned either by some Windows Client or by some DHCP server. To address this issue, Microsoft DNS servers have a DNS Scavenging / Zone Aging mechanism, which we may simulate by implementing a script, a configurable policy and a cron job. There seem to be best practices around to coordinate these scavenging intervals with lease times (For more details see the links noted at Ticket#2015100821000533).
> * In case the client registered it, he should clean it up, but usually he doesn't. Actually, as the details of Bug 39806 show, MS clients are well behaved citizens and try to do the clean up but are denied under certain conditions.
This issue has been filed against UCS 4.2. UCS 4.2 is out of maintenance and many UCS components have changed in later releases. Thus, this issue is now being closed. If this issue still occurs in newer UCS versions, please use "Clone this bug" or reopen it and update the UCS version. In this case please provide detailed information on how this issue is affecting you.