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New Member

BPDU

Hi all

this is regaring STP BPDU ...when i run a sniffer of my PC and sniff the THE ethernet ..i see BPDU messages there....y is this...?? y is my PC NIC recieving BPDU's??? it shud be with the swithces right

and tell me whether BPDU is sent on everyport??? i thought it shud be between the uplinks of the siwtches...and even i recieve ISL pakets...y is this??

Does BPDU whicgh is sent at every 2 sec add up to ur Trafic?

awaiting ur early reply

Regards

Raj

  • Other Network Infrastructure Subjects
3 REPLIES
Bronze

Re: BPDU

BPDU's are sent on every port by default. Otherwise a switch wouldn't be able to detect when another switch is added to the network. I would imagine BPDU's are included in a port's traffic statistics.

I don't know offhand why you're seeing ISL packets though.

New Member

Re: BPDU

Check to see if you port is a trunk port or if maybe it is set as a mirror port destination. Some higher end switches (ie 4006, 4500, 6500) can disable sending and recieving BPDU on specified or all ports.

New Member

Re: BPDU

Let's also not forget that BPDUs are multicast. In your sniffer trace, take a look at the IP and MAC addresses and you will see that they are indeed multicast.

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