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<p class="MsoNormal">Good afternoon folks!<o:p></o:p></p>
<p class="MsoNormal">We ran into a problem today and it has me completely dumfounded<o:p></o:p></p>
<p class="MsoNormal">Background:<o:p></o:p></p>
<p class="MsoNormal"> We create a host record for each device that connects to our network<o:p></o:p></p>
<p class="MsoNormal"> Over the years our dhcpd.conf file has grown due to little purging (yeah – I know we should be purging the data)<o:p></o:p></p>
<p class="MsoNormal">Symptom:<o:p></o:p></p>
<p class="MsoNormal"> Suddenly today, we began getting reports users are unable to get an IP address.<o:p></o:p></p>
<p class="MsoNormal"> The clients vary from iphones, to OS X and PC laptops<o:p></o:p></p>
<p class="MsoNormal"> The issue doesn’t seem to be OS or hardware dependent<o:p></o:p></p>
<p class="MsoNormal"> My logs are alerting:<o:p></o:p></p>
<p class="MsoNormal"> dhcpd: DHCPDISCOVER FROM xx:xx:xx:xx:xx:xx via x.x.x.x: uknown client<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:.5in;text-indent:.5in">In my dhcpd file there is a “host” record for each device – so I am scratching my head to why the device isn’t getting an IP address.<o:p></o:p></p>
<p class="MsoNormal"> Not all devices are having trouble getting IP leases
<o:p></o:p></p>
<p class="MsoNormal">Workaround:<o:p></o:p></p>
<p class="MsoNormal"> We have removed the directive in dhcpd.conf to “deny unknown clients”<o:p></o:p></p>
<p class="MsoNormal"> Now all of our devices are getting IP addresses.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Questions:<o:p></o:p></p>
<p class="MsoNormal"> Has anyone experienced a problem like this?<o:p></o:p></p>
<p class="MsoNormal"> If so, what did you find to be the root cause?<o:p></o:p></p>
<p class="MsoNormal"> Is it possible my 300k line dhcpd.conf file is causing this behavior?<o:p></o:p></p>
<p class="MsoNormal"> Could there be a programmatic time-out searching through host records in memory that is causing the host lookup to fail?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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