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I started to study networking and I have two cisco switches, and I want generate broadcast storm to test Spanning Tree, How do I do?

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up vote 6 down vote accepted

for gnu ping

ping -b -f <bcast addr>

This will flood ping the broadcast address however you must be the superuser to do so ( aka root ). In my very limited test sending 2 packets generated over 183 responses so make sure you do not do this on a production network for long.

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Ok, but, how Do I organize copper connections? look how it was: – marcello Feb 14 '12 at 22:45
I'd hook up a few client machines to the switches and boot them with a linux live cd. Should cause the effects you are looking for. – Lamar B Feb 14 '12 at 22:56
Adding a third switch may also help connected A to B, B to C, and C to A. May not be necessary though. – Lamar B Feb 14 '12 at 22:58

you can do it easily just disable spaning make loop , connect the tow switches using tow cables , and through console go to the ports which you connect to and disable apaning tree :

from switch console conf t

interface fastethernet (interface number)

spanin portfast

repeat this on all the ports connected between switchs , and switch will hang when connect your pc on any port

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