<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv=Content-Type content="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 12 (filtered medium)">
<style>
<!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:Tahoma;
panose-1:2 11 6 4 3 5 4 4 2 4;}
@font-face
{font-family:Consolas;
panose-1:2 11 6 9 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
p.MsoPlainText, li.MsoPlainText, div.MsoPlainText
{mso-style-priority:99;
mso-style-link:"Plain Text Char";
margin:0in;
margin-bottom:.0001pt;
font-size:10.5pt;
font-family:Consolas;}
span.PlainTextChar
{mso-style-name:"Plain Text Char";
mso-style-priority:99;
mso-style-link:"Plain Text";
font-family:Consolas;}
span.EmailStyle19
{mso-style-type:personal;
font-family:"Calibri","sans-serif";
color:windowtext;}
span.EmailStyle20
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
-->
</style>
<!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=WordSection1>
<p class=MsoNormal><span style='color:#1F497D'>I think Bjarne may have just
posted the solution to your problem this morning. Check the list for the
subject “Performance issue ( maybe ) - followup and solution”<o:p></o:p></span></p>
<p class=MsoNormal><span style='color:#1F497D'>His solution was to tune the
linux kernel.<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>
<p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
dhcp-users-bounces+rgrimsha=syr.edu@lists.isc.org
[mailto:dhcp-users-bounces+rgrimsha=syr.edu@lists.isc.org] <b>On Behalf Of </b>Nathan
McDavit-Van Fleet<br>
<b>Sent:</b> Thursday, November 11, 2010 4:45 PM<br>
<b>To:</b> 'Users of ISC DHCP'<br>
<b>Subject:</b> DHCP Drops Packets<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoPlainText>Hello All,<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>For some reason it appears as if our DHCP server 4.1.2 is
not responding to packets. We Wiresharked in front of the DHCP server and saw
that ~10 Discover packets were going into the server. Unfortunately only one of
those packets made it to the DHCP log itself. We’ve had similar issues with
DHCPRequest packets as well. We’ve been seeing a big delay for clients
trying to get an IP address.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Is this to do with the load of on the server itself? I
haven’t found a dependable recommendation for load averages, but for
example our leases file is 4.1MB and our lease time is 3600 seconds with about
3000 users or so.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>I also tcpdump’d the server and at least MORE of
the packets made it to the interface than made it to DHCPD. I disabled
iptables, added 255.255.255.255 to my hosts file and verified SELinux had the
exceptions needed.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Past that I don’t know where to turn.
Hopefully someone here has a suggest. <o:p></o:p></p>
<p class=MsoPlainText> <o:p></o:p></p>
<p class=MsoPlainText>Thanks,<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>-Nathan<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
</div>
</body>
</html>