Detecting The Source Of a Bridge Loop

[cadams]

Lets say that a device (switch) is not running STP and a look occurs somewhere on the network. What is the fastest way to detect the source of the loop?

[glen.grant · Accepted solution]

Usually you will only get a loop on devices that have redundant links , look at the interfaces and see if the counters are incrementing faster than it should , when all else fails you pull one side of any redundant links until you see the loop go away . If you have redundant links you should be running spanning tree . You can take a look here for more troubleshooting info on spanning tree . http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a00800951ac.shtml