I have set up port security on my catalyst to only permit 1 mac address. The mac address was learned dynamically as it is supposed to do. My question is on the 4000's if the link goes down due to a power failuer or some other unforseen act will the mac address stay in there or will it get erased since it as learned dynamically and I did not enter it manually.
I guess I don't see the security in that. If someone comes up and pulls the cable out of the port and waits 300 seconds(time the mac-address aging timer is set for). Then there is no longer any mac associated with that port and they can plug anything into that port and it will not shutdown.
If you unplugged the cable for 300 seconds as you suggested, this would not remove the MAC address from the CAM table. Shutting down the power on the switch is a different matter, this may clear the CAM table and allow you to attach another host to the port- but you have to break into the comms room in the first place to down the switch :-)
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