Increase CPU utilization

[vanferriols]

Hi,

We got sudden increase of CPU utilization in our Catalyst 4506 switch. The significant process have high percentage is Cat4k Mgmt LoPri.

details:

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27 1045559904 561416641 1862 76.99% 78.00% 78.41% 0 Cat4k Mgmt LoPri

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Do you have any ideas how we resolve this problem? I'm suspecting upgrading the IOS. But first, I need expert advice and suggestion.

Thanks!

Van

[sachinraja]

Hi Van,

If the CPU has increased after an IOS upgrade, revert back the old IOS and see if the problem resolves. Please check these things

1) check for bugs on the new IOS using the bug navigator.. reverting back to the old IOS will check the exact problem

2) make sure all debugs on the switch is turned off..

3) check for any security issue.. the cpu's can go up due to some excessive traffic on the switch, due to worms and viruses..

Open a tac case with cisco if not, and give them relevant outputs..

HTH

Raj

[vanferriols]

Hi Raj,

We used the latest IOS version and this is a bug that already fixed but I don't since we are experiencing increase in CPU. Also we have a significant number of Vlans implemented and says this problem easily reproduced. I tried also the work around but not successful. There are no excessive amount of traffic which causes the event. I suspect this will resolve by upgrading an IOS. Which I'm currently working with Cisco and waiting for their callback.

thanks for your input!

Van

[sachinraja]

Hi Van,

thanks for the update.. let us know once you resolve the issue, which will be helpful to others here.. rate replies if found useful..

Raj

[cezarmarson]

Hi guys I´m having the same problem in a Catalyst 4000 L3

how did you solved the issue? in my case it doesn´t seem to be a bug. There are 2 swiches running IOS 12.1 and 12.2 as long as they become the gateway of the network the high processing starts, see the output :

25 1592068280 36171459 44014 9.50% 6.01% 8.48% 0 Cat4k Mgmt HiPri

26 17764450601468886581 1209 58.96% 25.35% 43.08% 0 Cat4k Mgmt LoPri

any clue of solving the problem

tks

cezar

[vanferriols]

Hey Cezar,

We resolve it by upgrading the IOS of the switch to the latest version. Btw, what application your running in your switch and its setup. That would depend also the utilization of your switch.

Regards,

Van