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<p class="MsoNormal"><span style="color:#1F497D">I disabled update_optimization and as dhcp releases are renewed (I already has update_static enabled) we are re-creating the DNS entries.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I still have no idea why those entries all got deleted and am rather stressed over it.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Please help me to understand what went wrong, and how to prevent or properly fix.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Many thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Brian<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b>From:</b> dhcp-users-bounces@lists.isc.org [mailto:dhcp-users-bounces@lists.isc.org]
<b>On Behalf Of </b>Cuttler, Brian (HEALTH)<br>
<b>Sent:</b> Tuesday, June 09, 2015 12:05 PM<br>
<b>To:</b> Users of ISC DHCP<br>
<b>Subject:</b> dns_update_log shows dynamic entries deleted<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We are running on Centos 7.1 and have dhcp 4.2.5, with bind 9.9.4.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We are running dhcp with subnet 10.57.36.0/22 permitted dynamic dns udpates, except for the last 100 addresses in the pool, which we excluded to allow for static addresses that we needed.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Things have been working wonderfully – but at 08:18 this morning a large number of entries were removed from dynamic dns.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The dhcp clients were either, only asleep for the night (Windows, printers) or actually online (linux).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve no idea why these DNS entries were removed, exactly how to get them back, and how to prevent them from being removed again.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’d suspect it was a lease expiration issue, but these machines all check in and renew, at least they should be, I can check the boot.log and see.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for your help,<o:p></o:p></p>
<p class="MsoNormal">Brian<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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