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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Do you have MLD snooping turned on? If so, that could be an issue.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Frank<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> foundry-nsp [mailto:foundry-nsp-bounces@puck.nether.net] <b>On Behalf Of </b>Justin Keery<br><b>Sent:</b> Wednesday, November 19, 2014 4:04 AM<br><b>To:</b> foundry-nsp@puck.nether.net<br><b>Subject:</b> [f-nsp] ANY IDEAS - IP6 multicast traffic causing severe CPU load issue (on ICX)<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><br>Hi folks, any ideas about this?<br><br>The switches affected by this include ICX6540, 6610 and 6650 all of which were involved in transporting the VLAN described below.<br><br>IP6 multcast traffic (less than 20Mbit/sec, discovered with wireshark on a mirror port) on VLAN682 was causing >40% CPU load on all switches where this VLAN was configured, even though there is no IP virtual interface in this VLAN. At one point there was a brief but serious OSPF failure whilst this condition was present. <br><br>With the ingress port shut down the CPU load returned to 1%.<br><br>We tried to disable IP4 and IP6 igmp / mld snooping, this had no effect. We then added a router-interface so we could add an IP6 ACL to filter *all* IP6 traffic - again no effect<br><br>vlan 682 name KARMARAMA_L2_ONEA809159_682 by port<br> tagged ethe 1/2/1 to 1/2/3<br> router-interface ve 682<span style='color:red'> <- added later so we could implement an ACL</span><br> multicast disable-igmp-snoop <span style='color:red'><- did not help</span><br> multicast6 disable-mld-snoop <span style='color:red'><- did not help</span><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><b>We need a way to make sure that IP6 multicasts on a VLAN won't overload the CPU on any switch with that VLAN present - ideally filter that VLAN from the CPU altogether!</b><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Any ideas?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Justin<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>