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<p class="MsoNormal"><span style="font-size:11.0pt">I wanted to follow up to my own post in case someone else encounters this issue in the future. The problem I discovered was that DHCPD keeps a record of the last lease for a given client forever so that it
can try to give the client that address again. We had over 300,000 leases in the leases file that were in a binding state other than active (e.g. expired, free). The majority of these were no doubt from client devices that will not ever show up on our network
again. At the end of the semester, I stopped the primary and failover servers and ran a Perl script I wrote to go through and get rid of all these inactive leases. The load times changed to seconds and we have suffered no ill effects in the nearly one month
since I did this.<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:black">Shane Merritt
</span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:black">Office of Information Technology
<br>
The University of Alabama<br>
smerritt@ua.edu </span><span style="font-size:12.0pt;color:black"><o:p></o:p></span></p>
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<b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">dhcp-users <dhcp-users-bounces@lists.isc.org> on behalf of Shane Merritt <smerritt@ua.edu><br>
<b>Date: </b>Thursday, August 4, 2022 at 2:01 PM<br>
<b>To: </b>dhcp-users@lists.isc.org <dhcp-users@lists.isc.org><br>
<b>Subject: </b>[EXTERNAL] extremely slow DHCPD startup time<o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt">I have a failover pair of DHCP servers running 4.4.2-P1 that handle a DHCP for a very large wireless network (>75k devices active at any time). The leases file on these boxes is around
200 megabytes. The problem I am having is when I need to make a change and restart, DHCPD takes over 25 minutes to start giving out addresses. I assume this is due to the large lease file. I see that there are tons of leases in the file that are “binding
state free” that in some cases are months old. Are there any suggestions to improve this situation?</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:black">Shane Merritt
</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:black">Office of Information Technology
<br>
The University of Alabama<br>
smerritt@ua.edu </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:.5in"><b><span style="font-size:12.0pt;font-family:Helvetica;color:#990000"> </span></b><span style="font-size:12.0pt"><o:p></o:p></span></p>
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