Re: Portfast Clarification

Portfast disables spanning-tree. Bpdu-guard is used on a root brigde
to protect it from being overthrown by a switch with lower root id.
Bpdu filter will listen for bpdu trafic on the ports it's configured
and drop it. Your number 1 observation is right. This features are not
enabled automatically after enabling portfast.

Observation 2. Since portfast disables spanning tree, a switch plugged
into such port runs the risk of loop because it doesn't know where to
"fall" the tree. And this ports will stay the way they are until you
intervain by changing the port state.

Sent from my Iphone.
On Nov 30, 2009, at 9:10 PM, Sarad <tosara_at_gmail.com> wrote:

> Hi Experts,
>
> I have created some labs on stp portfast & had some observations. I
> would
> like to verify whether my observations are correct with you all. My
> observations are as follows.
>
>
> 1. If I enable portfast default on the switch or portfast on a
> particular
> interface will BPDU filter or BPDU gurad get enable by default
> (irrespective
> of trunk or access port)?My observation is no
>
>
> 2. If not it will create a temporary loop on the network if there are
> switches configured on the ports with portfast enable but after few
> seconds
> stp will run on those ports & move those ports to forwarding or
> blocking
> stage.
>
> Thank you in advance
>
> Sara
>
>
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Received on Mon Nov 30 2009 - 21:34:07 ART