<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:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
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;}
span.E-MailFormatvorlage17
{mso-style-type:personal-compose;
font-family:"Verdana","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:70.85pt 70.85pt 2.0cm 70.85pt;}
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="DE" link="blue" vlink="purple">
<div class="WordSection1">
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">we have a setup with two varnish servers (version 3.0.2) and two backend servers. This setup works fine, if we split the requests with an loadbalancer to the
two varnish servers. Around 500req/s 20MBit/s bandwidth on each server.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">In Addition we have defined a backend probe which will tests the backend each 10s. This also works fine.
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Now, if we switch all requests to one varnish server, after some time (around 20 seconds) the backends will be marked as sick, but they are both up and answering
all requests. Also without any backend probe defined in VCL, varnish gets in trouble serving content. Some months ago, we had no problems with this and served more than 400Mbit/s from one single server.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">What could be the bottleneck?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Kind regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black">Thomas Winkelmann</span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black">Web-Entwickler</span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">___________________________________<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">FFH Digital<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black">Radio/Tele FFH GmbH & Co.
</span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black">Betriebs-KG<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">FFH-Platz 1, 61111 Bad Vilbel<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Tel.: 06101 / 988 – 346<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Fax: 06101 / 988 – 555<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">Email:
</span><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><a href="mailto:t.winkelmann@FFH.de"><span lang="EN-US" style="color:blue">t.winkelmann@FFH.de</span></a></span><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif"">FFH Digital – Die Webradios<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><a href="http://www.FFH-Digital.de"><span style="color:blue">www.FFH-Digital.de</span></a><span style="color:black"><o:p></o:p></span></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif";color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">HIT RADIO FFH<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><a href="http://www.FFH.de"><span lang="EN-US" style="color:blue">www.FFH.de</span></a></span><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">planet more music radio<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><a href="http://www.planetradio.de"><span lang="EN-US" style="color:blue">www.planetradio.de</span></a></span><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif"">harmony.fm – Hessens Greatest Hits<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Verdana","sans-serif""><a href="http://www.harmonyfm.de"><span lang="EN-US" style="color:blue">www.harmonyfm.de</span></a></span><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Verdana","sans-serif""><o:p> </o:p></span></p>
</div>
<br>
<hr>
<font face="Arial" color="Black" size="1">RADIO / TELE FFH GmbH & Co. Betriebs-KG<br>
FFH-Platz 1, 61111 Bad Vilbel<br>
HRA - Nr. 26092 Frankfurt/Main<br>
USt.IdNr. DE 112152620<br>
Geschäftsführer / Programmdirektor: Hans-Dieter Hillmoth<br>
</font>
</body>
</html>