Catalyst 6509-E High CPU (VSS)

[chanseeyee]

Dear all experts,

We are currently facing high CPU in our core switch Catalyst 6509-E (VSS).. Kindly refer to attached for details.. Appreciate if you could help us on this matter.. Thank you very much

[Mark Malone]

Total CPU Utilization: 99%
  Process Utilization: 10%
  Interrupt Utilization: 89%

Have you got CEF enabled ? Are the interfaces running high?

couple good docs on cpu for vss/6500s

https://supportforums.cisco.com/document/53866/troubleshooting-high-cpu-under-interrupts-7600-and-6500-boxes-using-debug-netdr-tool

http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/63992-6k-high-cpu.html

[chanseeyee]

Hi Mark,

Thanks for your reply.. Currently, we have configured "platform ip cef load-sharing ip-only".. As for now, we do not see the interfaces with high utilization.. Is this cosmetic bug? as the cpu only about 10% utilization, when we sum of all the values from the processes.. thank you very much for your kind assistance

[Mark Malone]

Hey is ip cef enabled globally as well ?if not I would apply it and see if it helps bring the interrupts down, It could be a bug you could check the IOS version release guide online that your running it may be something known for that specific version but you would want to make sure the switch is not switching traffic incorrectly as well , are you seeing any degradation when you going through the switch, is there any noticeable delays as cpu that high would make the switch slow to login to etc

a few types of configuration can cause it as well , using ip redirects, adding log to acls these can cause packets to be punted to the RP instead of the SP which will cause cpu to spike that high the netdr will be able to tell you if packets are being punted incorrectly