glen.grant Sun, 04/09/2006 - 04:07
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Look at all your interfaces , one of them is probably high and for some reason it looks like it is having to process switch all the traffic , could be anything like a virus etc... Look for a high amount of drops and throttles on a particular interface.

Bobby Thekkekandam Sun, 04/09/2006 - 04:14
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Looking at the "show proc" output, the "95%/0%;" tells me that the utilization is mainly process related rather than interrupt related. the number after the '/' is traffic switched under interrupt.

To troubleshoot further we'll need to look at the individual processes and see which are elevated. could you attach a "show proc cpu"?



jawwalit Sun, 04/09/2006 - 04:19
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this l3 switch is the core switch for our company and also i have another one use as standby (hsrp) it the other one have low utilization how can i split the processing between as to reduce the utilization on the main one

i sent also another file it may contain a useful information this file on the main switch which have the high utilization


Bobby Thekkekandam Sun, 04/09/2006 - 04:49
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Looking at that output, I see that

"K2L2 Address Table R" is at 47.88%.

This process is related to L2 entries and adjacency updates. The learning of MAC addresses on this box is done in software, so if we keep on learning too many mac addresses you will see a spike of CPU on this process. This may happen in the following


- constant receipt of spanning tree topology change BPDUs: on PVST that reduces cam aging and you will see entries being deleted rapidly, on rapid-PVST/MST this flushes the entries. Overall a number of entries may need to be deleted/added again. Make sure you have "switchport host" configured on ports which directly connect to end devices. This will avoid TCN generation when a workstation reboots.

- mac-address moves: where a user will move from one port to another, or a mac address may be looping in the network

Check for TCNs in the network as well as any %C4K_EBM-4-HOSTFLAPPING messages in the log.



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jawwalit Sun, 04/09/2006 - 05:02
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this happen only when i use a trunk and vlan on the switch how can i reduce the followinh logs is produce by the switch:

mahmoodmkl Sun, 04/09/2006 - 05:17
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There is a loop in u r network.if u have redundant links disconnect one by one and check if the cpu level goes down.




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