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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is issue that linux DHCP is sending wrong parameters while sending offer packet for Cisco AP’s in one of our office locations.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have taken packet captures on the DHCP server side.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As you can see in below packet capture there is DHCP DISCOVER message from Cisco AP requesting for IP and other parameters.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Then in DHCP offer packet, it offers IP from correct subnet, but with wrong router IP, subnet mask and broadcast address.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Basically, my observation is that it is giving wrong parameters in offer from the topmost subnet (as linux works from top to bottom approach) that has cisco option 43 configured. If I remove the Cisco option 43 from that subnet then it
provides parameters from next subnet which has the Cisco option 43 in it.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The correct subnet from which I am expecting that the AP should get all its parameters is configured at the end of the DHCP conf file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>DHCP DISCOVER PACKET<o:p></o:p></b></p>
<p class="MsoNormal"><b><o:p> </o:p></b></p>
<p class="MsoNormal"><img width="803" height="819" style="width:8.3645in;height:8.5312in" id="Picture_x0020_2" src="cid:image001.png@01D4B4D9.6F320900"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>DHCP OFFER PACKET<o:p></o:p></b></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><img width="943" height="885" style="width:9.8229in;height:9.2187in" id="Picture_x0020_3" src="cid:image002.png@01D4B4D9.6F320900"><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">Best regards,</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">Yogesh Gaikwad</span></b><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">, Technical Architect - TECA Network</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">Tieto Corporation, TSM</span></b><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">email
<a href="mailto:Yogesh.Gaikwad@tieto.com" target="_blank"><span style="color:blue">Yogesh.Gaikwad@tieto.com</span></a>, direct +91 (0)2067303120</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif;color:#444444">Wing 1, Cluster D, EON Free Zone, MIDC Kharadi Knowledge Park, Pune - 411 014, India<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:7.0pt;font-family:"HelveticaNeueLT Std";color:black;mso-fareast-language:CS"><o:p> </o:p></span></p>
<p class="MsoNormal"><a href="http://www.tieto.com/"><span lang="CS" style="font-size:7.0pt;font-family:"HelveticaNeueLT Std";color:black;mso-fareast-language:CS;text-decoration:none"><img border="0" width="85" height="33" style="width:.8854in;height:.3437in" id="Picture_x0020_1" src="cid:image003.png@01D4B4D9.6F320900" alt="Tieto_logo_for_email_signature_127x50"></span></a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#444444">Please note: The information contained in this message may be legally privileged, confidential and protected from disclosure. If you received this in error, please
notify the sender immediately and delete the message from your computer. Thank you.</span><span style="font-size:8.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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