how we can increase CPU utilization to max(above 90%) for cisco switch 2960? IOS switch.

[Jagzz]

Hi,

For my testing, I needs to increase my cisco switch CPU utilization to more then 90%. Could someone can help me? what are the possibility ways to increase?

I have tried with "debug all", once i passed the commend, i could not able to establish the connection with switch.

Then if i connect back after few hours i can see CPU utilization 5% last 5min.

I want switch should be stay 90% CPU utilization log time.

Could someone assist me how i can archive this condition?

[Joseph W. Doherty]

Why?

Reason I ask, what you're asking for might be used as a DoS (denial of service) attack.

[Reza Sharifi]

Hi,

What are trying to accomplish with high CPU usage?

You can create loop but connecting 2 ports together and turning of STP but not sure if you can access the switch.

HTH

[paul driver]

Hello

Attach two links between two switches in the same vlan, create L3 svi for that vlan on each switch then disable spanning-tree for that vlan and initiate a ping to the ip address for that vlan, or just have those two same links set as trunks with stp disabled, either way that should do the trick!

[mahazz12]

Hi, I also wanted to increase CPU utilization of my cisco switch (Cisco Catalyst C9300) for which I tried disabling STP which did increase CPU utilization to about 40%, however every time it resulted in losing my SNMP connection to which my monitoring tool and switch were connected, hence I am unable to further monitor the switch (for throughput etc). Can you help me out with why it keeps losing connection and how can I maintain it or any other suggestions that you have. 

Below is the link for reference for the question I posted. Your help will be much appreciated. TIA.

https://community.cisco.com/t5/other-network-architecture-subjects/need-help-in-increasing-cpu-utilization-for-cisco-switch/td-p/4908233

[Joseph W. Doherty]

Why the new reply here?

". . . I tried disabling STP which did increase CPU utilization to about 40%, however every time it resulted in losing my SNMP connection to which my monitoring tool and switch were connected, hence I am unable to further monitor the switch (for throughput etc). Can you help me out with why it keeps losing connection and how can I maintain it or any other suggestions that you have."

Well, yea, when you push CPU up, control-plane functions, like SNMP, tend to "break".

What are you trying to accomplish?

[Leo Laohoo]

You want to generate high CPU? Easy: STP Loop

[Jagzz]

Thanks for the replay.

How we can do STP loop?

[paul driver]

Hello

See my previous post -  basically disabling spanning-tree and having dual links interconnected between two switches as trunks