Spanning tree BPDU guard

carl_townshend · ‎07-10-2008

Hi all, can anyone tell me why i would put this on my switch ports? it it advisable to do so?

cheers

andrew.prince · ‎07-10-2008

BPDU Guard is used on switch ports put into "spanning-tree portfast" - so IF you connect another switch into a portfast port, they will not interfere with STP. Switch will ignore ANY BPDU's recevied on the interface.

It is adviable to do so - if you have switchports in spanning-tree portfast".

It does not hurt to enable it:-

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a008009482f.shtml

HTH.

srue · ‎07-10-2008

bpduguard will errdisable the port if it receives any bpdu's on the port its configured on. bpdufilter will simply ignore/drop any bpdu's that it receives without errdisabling the port.

depending on what you want to accomplish either of these might suit your needs. i've implemented bpduguard on all switch ports in some implementations, except where bdpu filtering is needed.

carl_townshend · ‎07-10-2008

so can we only use bpdu guard on portfast ports? why only portfast ports?

also, what is bpdu filter for, why would we need to filter bpdu's ?

andrew.prince · ‎07-10-2008

Read the url previously provided.

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a008009482f.shtml