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High CPU usage (catalyst 3750)

hi,

I just put a new catalyst 3750 in production. The strange thing is that it has very high CPU usage, running under following conditions :

~600 hosts, ~15 Mbps traffic, sdm preffer vlan

#sh ver Cisco IOS Software, C3750 Software (C3750-ADVIPSERVICESK9-M), Version

12.2(25)SEC1, RELEASE SOFTWARE (fc1) Copyright (c) 1986-2005 by Cisco Systems, Inc. Compiled Fri 29-Jul-05 22:36 by yenanh

ROM: Bootstrap program is C3750 boot loader BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.1(14r)EA1a, RELEASE SOFTWARE (fc1)

The main consumer is HL3U (probably Hardware Layer 3 U!!), for wich neither google nor cisco.com has any info!!?

#sh processes cpu sorted CPU utilization for five seconds: 45%/31%; one minute: 54%; five minutes: 53% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 102 426513 25762 16555 8.61% 11.93% 12.03% 0 HL3U bkgrd proce 145 15323 71507 214 0.31% 0.12% 0.14% 0 IP Input 132 4300 735 5850 0.15% 0.01% 0.02% 0 Exec 107 3359 798795 4 0.15% 0.04% 0.02% 0 Hulc LED Process 111 929 6781 137 0.15% 0.03% 0.00% 0 HQM Stack Proces 6 0 2 0 0.00% 0.00% 0.00% 0 Timers 5 9 2 4500 0.00% 0.00% 0.00% 0 Pool Manager 8 0 1 0 0.00% 0.00% 0.00% 0 AAA_SERVER_DEADT 4 26629 3607 7382 0.00% 0.13% 0.07% 0 Check heaps

Any ideas about possible reasons and solutions? I have similar 3750 switch running wich handles much more traffic, hosts and BGP sessions and it is ~8-10% cpu usage ?!?!

Reply to
rootcho
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um~~,you may need try :ip cef

Reply to
WanderDragon

virus?worm?

Reply to
WanderDragon

hmm.. no, I found the problem :"( the switch is VLAN mode in which all the routing is done in CPU, very annonying I needed it in VLAN mode (now how to use it in DEFAULT)...:"(

Reply to
rootcho

Hi,

What is vlan mode?

I have had a short look on CCO and can find no reference to it as an operational mode. (It is a configuration mode)

I have used a few 3750's with VLANS and have seen hardware based CEF switching operating as I would expect.

By the way: "CPU utilization for five seconds: 45%/31%; one minute: 54%; five minutes: 53%"

45%/31% indicates that the total load was 45% of which 31% was at "Interrupt Level" i.e. 31% of the CPU was being used for processor based Speedy Switching. Where 'Speedy' is one of "Fast", "Optimum", "NetFlow" or "CEF".
Reply to
anybody43

Why you need it in a VLAN SDM template?

If the reason for keeping switch in VLAN template is because routing and default templates does not have enough hw resources for your needs then you need to add another switch to do some load balancing or upgrade to a bigger platform (i.e. 4500)...

B.R. Igor

Reply to
Igor Mamuzic

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