CPU utilisation high

[smartboy2255]

Dear all,

         I am getting CPU utilisation high on my cisco switch 4500.Pls find the logs attached.its showing L3 fwd low is showing more...Logs is attached..Pls help me troubleshoot the same

CPU utilization for five seconds: 82%/6%; one minute: 83%; five minutes: 83%

PID Runtime(ms)   Invoked      uSecs   5Sec   1Min   5Min TTY Process

  30   211726196 804002723        263 63.03% 64.09% 63.54%   0 Cat4k Mgmt LoPri

  29  17244100122930251134          0  5.75%  6.05%  5.99%   0 Cat4k Mgmt HiPri

Packets Received by Packet Queue

Queue                  Total           5 sec avg 1 min avg 5 min avg 1 hour avg
---------------------- --------------- --------- --------- --------- ----------
Esmp                        1703899410       102        90        72         71
Control                     1234934837       124       110        88         76
Host Learning                 24185925         3         2         0          0
L3 Fwd High                        921         0         0         0          0
L3 Fwd Medium                      108         0         0         0          0
L3 Fwd Low                149572335413     50861     49117     38987      37780

CPU utilization for five seconds: 82%/6%; one minute: 83%; five minutes: 83%

PID Runtime(ms)   Invoked      uSecs   5Sec   1Min   5Min TTY Process

  30   211726196 804002723        263 63.03% 64.09% 63.54%   0 Cat4k Mgmt LoPri

  29  17244100122930251134          0  5.75%  6.05%  5.99%   0 Cat4k Mgmt HiPri

Thanks in advance....

Regards,

Ajith

[Reza Sharifi]

Have a look at this document for troubleshooting tip and resolution

http://www.cisco.com/en/US/products/hw/switches/ps663/products_tech_note09186a00804cef15.shtml

HTH

[smartboy2255]

HI Reza,

   Already I have gone through the above link.I have done all testing except CPU SPAN.I would like to know wat type of traffic normally passing through L3 FWD LOW.Since that value is showing more.

***********************************************************************************

Packets Received by Packet Queue

Queue                  Total           5 sec avg 1 min avg 5 min avg 1 hour avg
---------------------- --------------- --------- --------- --------- ----------
Esmp                        1703556305        82        87        73         71
Control                     1234523753        96       103        88         76
Host Learning                 24170396         2         1         0          0
L3 Fwd High                        921         0         0         0          0
L3 Fwd Medium                      108         0         0         0          0
L3 Fwd Low                149403909597     40344     46333     38735      37728

Regards,

Ajith

[smogra]

Answering to your question,

L3 Fwd Low :
Packets that must be forwarded in software, such as GRE4 tunnels. 
If the ARP5 is unresolved for the destination IP address, packets 
are sent to this queue.

So, a SPAN is definitely needed to find out the kind of traffic CPU is 
hitting.

Cheers 
Sweta

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