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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-GB link=blue vlink=purple><div class=WordSection1><p class=MsoNormal style='margin-left:36.0pt'><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:EN-GB'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext;mso-fareast-language:EN-GB'> Pavel Levshin [mailto:pavel@levshin.spb.ru] <br><b>Sent:</b> 25 March 2011 19:50<br><b>To:</b> pacemaker@oss.clusterlabs.org<br><b>Subject:</b> Re: [Pacemaker] IPaddr2 Netmask Bug Fix Issue<o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'><o:p> </o:p></p><p class=MsoNormal style='margin-left:36.0pt'>25.03.2011 18:47, <a href="mailto:Darren.Mansell@opengi.co.uk:">Darren.Mansell@opengi.co.uk:</a> <o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";mso-fareast-language:EN-GB'><br><br><o:p></o:p></span></p><p class=MsoNormal style='margin-left:36.0pt'>We configure a virtual IP on the non-arping lo interface of both servers and then configure the IPaddr2 resource with lvs_support=true. This RA will remove the duplicate IP from the lo interface when it becomes active. Grouping the VIP with ldirectord/LVS we can have the load-balancer and VIP on one node, balancing traffic to the other node with failover where both resources failover together.<o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'> <o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'>To do this we need to configure the VIP on lo as a 32 bit netmask but the VIP on the eth0 interface needs to have a 24 bit netmask. This has worked fine up until now and we base all of our clusters on this method. Now what happens is that the find_interface() routine in IPaddr2 doesn’t remove the IP from lo when starting the VIP resource as it can’t find it due to the netmask not matching.<o:p></o:p></p><p class=MsoNormal style='margin-left:36.0pt'><span style='font-size:12.0pt;font-family:"Times New Roman","serif";mso-fareast-language:EN-GB'><br>Do you really need the address to be deleted from lo? Having two identical addresses on the Linux machine should not harm, if routing was not affected. In your case, with /32 netmask on lo, I do not foresee any problems.<br><br>We use it in this way, i.e. with the address set on lo permanently.<br><br><br>--<br>Pavel Levshin<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'>Thanks Pavel,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'>However, this means I would have to disable LVS support for the resource. Which means that to make it work with LVS I have to set lvs_support to false.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'>Of course, I’ll do whatever it takes on my set up to make it work, but it’s not intuitive for other users.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'>Regards<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D;mso-fareast-language:EN-GB'>Darren Mansell<o:p></o:p></span></p></div></body></html>