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New Member

Cpu of cisco switch high.

Wse have a WS-C3548-XL-EN switch whose cpu utilization reasches 99 % dails between 12:30 hrs to 1:00 hrs. When chcked it shows that address learning process is occupying most of the cpu.

Have checked that none of the port on the switch goes down or comes up at this period.

Can someone help me to understand the address learning process.


Re: Cpu of cisco switch high.

Do you see any address relearning in your syslogs during the same time?

Can you please post or attach the output of Sh proc cpu & show logging command


Re: Cpu of cisco switch high.


Please go thrugh the link below :

HTH, Please rate if it does.

-amit singh

New Member

Re: Cpu of cisco switch high.

Hello there,

write a little script to do a show proc cpu sort every 3 or 5 minutes and then see what processes other than address learning are making the box gain the high cpu.

what kind of End user connectivity is there to this box. do you have it connected to PCs or do you have a layer 2 connection to another provider ?

also narrow down on the ports that are tryin to do the relearning; generally would be a case of your service providers switch being screwy ( i am assuming that you have this switch connect to some sort of a service provider) or other switches in its diameter going throught a storm? ( a case that would happen ocassionally but happening dialy in your case might not apply in this scenario)