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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal">I have a question about mecanism for requests of long subdomains FQDN.<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">Our DNS, which is in recursive configuration, split long fqdn request with subdomains requests like :<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">Original request from the client to our recursive DNS :
<i>A a.b.c.d.example.com<o:p></o:p></i></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">Requests done by our DNS to the domain example.com NS:<o:p></o:p></span></p>
<p class="MsoNormal"><i><span style="mso-fareast-language:FR">A _.c.d.example.com<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="mso-fareast-language:FR">A _b.c.d.example.com<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="mso-fareast-language:FR">A a.b.c.d.example.com<o:p></o:p></span></i></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">Is it a normal behaviour ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">This is only done for 4 levels domains (a.b.example.com for example) and more, not « normal » fqdn (ex : www.example.com).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">What part of the configuration manage this mecanism ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">Is this really usefull ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR">It is problematic for DNSBL requests because it generate a lot of useless requests and this kind of service look at the number of requests done (usage policy):<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><img width="1315" height="158" style="width:13.6979in;height:1.6458in" id="Image_x0020_3" src="cid:image002.png@01DBC5B3.192E1570"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:FR"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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