I had a switchport shut down today due to an unexpected bpdu - and I have bpduguard enabled. Turns out it was a 7940 phone on that port...do the 7940's send bpdu's or would someone have to have plugged something into the switchport on the phone for this to happen?
It has happened that the user sitting at the desk where the IP phone is connects one of the free cables connected to another jack to the "computer port" on the IP phone and of course the cable from the jack is connected to a switchport, this will trigger the bdpuguard violation. All of this is good because otherwise it could have caused a network loop.
BPDU guard is a matter of enforcing a policy, not preventing loop. It's not because that you received a BPDU that there was redundancy. And if there is redundancy detected in the content of a BPDU, STP is responsible for breaking the loop.
So don't consider that BPDUguard saved you from a loop. BPDU guard reacted to a security policy that prevents a device running STP from connecting to your access port.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.