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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>Exactly – changing the service identifier option changes the SID, but not the source IP. Only way to change the srouce IP is have something manipulate the packet, such iptables or some other translation device.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>Frank<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'><o:p> </o:p></span></p><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"'> neeraj jain [mailto:neerajjain_iet@yahoo.com] <br><b>Sent:</b> Thursday, June 09, 2011 3:40 AM<br><b>To:</b> Users of ISC DHCP; frnkblk@iname.com<br><b>Subject:</b> RE: Corosyn for DHCP failover<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0><tr><td valign=top style='padding:0in 0in 0in 0in'><p class=MsoNormal>Hi Frank,<br><br>I don't understand you completely but can you tell me if I can use my virtual ip to reply for the Discover request.<br><br>I tried with the service identifier option but it only changes the SID of the packet but not the source ip of the packet. <br><br>I am sure it has to do something with corosync VIP configuration but not finding the clue.<br><br>Thanks in advance,<br>Neeraj Jain<br><br>--- On <b>Thu, 9/6/11, Frank Bulk <i><<a href="mailto:frnkblk@iname.com">frnkblk@iname.com</a>></i></b> wrote:<o:p></o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'><br>From: Frank Bulk <<a href="mailto:frnkblk@iname.com">frnkblk@iname.com</a>><br>Subject: RE: Corosyn for DHCP failover<br>To: "Users of ISC DHCP" <<a href="mailto:dhcp-users@lists.isc.org">dhcp-users@lists.isc.org</a>><br>Date: Thursday, 9 June, 2011, 9:19 AM<o:p></o:p></p><div><p class=MsoNormal>The appliance we use does iptables to mangle the packets. We had this same<br>issue with a piece of access gear that requires the source IP of the DHCP<br>responses to match the IP address it relayed it to.<br><br>Frank<br><br>-----Original Message-----<br>From: dhcp-users-bounces+frnkblk=<a href="/mc/compose?to=iname.com@lists.isc.org">iname.com@lists.isc.org</a><br>[mailto:dhcp-users-bounces+frnkblk=<a href="/mc/compose?to=iname.com@lists.isc.org">iname.com@lists.isc.org</a>] On Behalf Of<br>Glenn Satchell<br>Sent: Tuesday, June 07, 2011 8:13 AM<br>To: Users of ISC DHCP<br>Subject: Re: Corosyn for DHCP failover<br><br>On 06/07/11 21:47, neeraj jain wrote:<br>> Hi all,<br>> I am tring to use the corosync for the dhcp failover instead of DHCP<br>> failover configuration. I am able to run the dhcp with the corosync<br>> successfully and tested the failover also. Corosync assign the VIP and<br>> switch in case of failover. I am also using rsync to synchronize the<br>> configurations and lease file.<br>> Only problem is that when my relay agent send the DHCP discover request<br>> at VIP, my dhcp server reply with offer using the physical ip of the<br>> machine.<br>> What I need is the discovery and offer should happen at the same VIP. I<br>> am not sure why DHCP is using physical ip to reply for the request.<br>> Even I am not sure if this the correct forum to raise this question but<br>> help me in case someone has faced the same problem.<br>> Thanks in advance,<br>> Neeraj jain<br>><br>><br><br>Hi Neeraj<br><br>Depending on your operating system, the usual behaviour for any socket <br>is to use the first IP assigned on that interface as the source address.<br><br>You can override this to some extent using the 'server-identifier' <br>setting in dhcpd.conf. See the man page for full details.<br><br>Note that this doesn't necessarily change the source IP address of <br>packets from the server, but it sets an internal dhcp option so that the <br>client will use this address when contacting the server.<br><br>-- <br>regards,<br>-glenn<br>_______________________________________________<br>dhcp-users mailing list<br><a href="/mc/compose?to=dhcp-users@lists.isc.org">dhcp-users@lists.isc.org</a><br><a href="https://lists.isc.org/mailman/listinfo/dhcp-users" target="_blank">https://lists.isc.org/mailman/listinfo/dhcp-users</a><br><br>_______________________________________________<br>dhcp-users mailing list<br><a href="/mc/compose?to=dhcp-users@lists.isc.org">dhcp-users@lists.isc.org</a><br><a href="https://lists.isc.org/mailman/listinfo/dhcp-users" target="_blank">https://lists.isc.org/mailman/listinfo/dhcp-users</a><o:p></o:p></p></div></td></tr></table><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif"'><o:p> </o:p></span></p></div></body></html>