CEF not working on Catalyst 3750 (L3) with EMI image

[bgandhi]

Hi,

I have a Cisco 3750 switch peering with Internet Service provider using BGP. When I start learning BGP routes, the CPU utilization shoots to 99 %. On analysis, we observed that Interrupt utilization is high and packets are getting process switched not cef switched. This is not happening on Cisco 3750 switch and working fine on Cisco 3660 router.

Kindly suggest if anybody knows the solution.

Regards,

Bhavesh

[globalnettech]

Hello Bhavesh,

when you do a 'show proc cpu', which processes are actually causing the high CPU ? Just in case it is the BGP Scanner or BGP router process, you might want to check this document:

Troubleshooting High CPU Caused by the BGP Scanner or BGP Router Process

http://www.cisco.com/en/US/partner/tech/tk365/technologies_tech_note09186a00801c4f48.shtml

Regards,

GNT

[bgandhi]

Hi,

Actually none of the processes show high utilization. It is high utilization in interrupts.

Regards,

Bhavesh

[amit-singh]

Hi Bhavesh,

Please let me know the SDM template you are running on the switch. It defaults to desktop.

As you are running BGP on this 3750. I would recommend you to reconfigure SDM template to routing.

Sample configs:

3750-B#conf t

Enter configuration commands, one per line. End with CNTL/Z.

3750-B(config)#sdm prefer ?

default default bias

routing unicast bias

vlan vlan bias

3750-B(config)#sdm prefer routing

The switch needs to be rebooted for the new SDM template to take effect. You can read more

about SDM templates on CCO at

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat3750/12225se/3750scg/

swsdm.htm

HTH, Please rate if it does.

-amit singh

[bgandhi]

Hi Amit,

Thanks for the useful information. I have configured the same but it didnot help.

Regards,

Bhavesh

[bgandhi]

Hi Amit,

Yesterday we again tried enabling BGP and imported around 3000 routes but CPU utilization did not shoot. However, the cef entries are still the same. Since the CPU utilization is under control, my problem is resolved.

Thanks for your valuable input.

Regards,

Bhavesh