Re: Portfast in Trunk port

The main application is just to avoid the normal STP process to allow
access to the network faster (No 30 second delay on plugging in).
Generally, it is only used when the device connected is something that
definitely will not cause a loop -- VMware hosts perhaps that you
trunk to, IP phones, other such widgets that talk 802.1q but are
actually end host devices, etc ... if you are doing this towards a
switch you better make damn sure there are no physical loops.

HTH

On Sun, May 6, 2012 at 7:31 AM, Carlos G Mendioroz <tron_at_huapi.ba.ar> wrote:
> Your customer should not be bridging those interfaces, so one going down
> will not "change the world" for STP.
> If he is doing a LAG, he should take care of migrating the MACs to the
> surviving link, usually by imposting some traffic.
>
> What kind of "STP inconsistent information" are you envisioning?
>
> -Carlos
>
> CCIE KID @ 05/05/2012 02:39 -0300 dixit:
>
>> Hey Marko
>>
>> Yes My SP has two customer facing interfaces and the customer facing
>> interfaces are trunk ports and they configure Portfast on these
>> interfaces.
>> Port fast configured interfaces still receive BPDUs but tat port doesnt
>> participate in STP Transition states. So my Customer Access laer goes
>> down,
>> this info will not be propogated in STP and there may be inconsistent
>> information in MAC Address table formed by STP
>>
>> Can u explain me exactly what is the actual application ?
>>
>> Thanks guys for ur thoughts :)
>>
>> On Sat, May 5, 2012 at 5:22 AM, Marko
>> Milivojevic<markom_at_ipexpert.com>wrote:
>>
>>> On Fri, May 4, 2012 at 11:00 AM, Anthony Sequeira
>>> <terry.francona_at_gmail.com> wrote:
>>>>
>>>> I am pretty sure this could be beneficial in a router on a stick
>>>
>>> scenario. So that of course begs the
>>>>
>>>> question - who the ^%&$ would do that in production.
>>>
>>>
>>> If you're an SP - customer-facing interfaces in the access layer, for
>>> example :-)
>>>
>>> --
>>> Marko Milivojevic - CCIE #18427 (SP R&S)
>>> Senior CCIE Instructor - IPexpert
>>>
>>
>>
>>
>
> --
> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>
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