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RE: vlan dot1q tag native posted 08/24/2007
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It's 2007, I used L3 routed links...

Why do we ever need end to end vlans? Local vlan's only for me...



-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of Toh
Soon, Lim
Sent: Friday, August 24, 2007 2:30 AM
To: sheherezada@xxxxxxxxx
Cc: Ajay Prakash; slevin kremera; Cisco certification
Subject: Re: vlan dot1q tag native

Hi All,

Thanks for sharing.

I used to think that we can easily VLAN-hop across 802.1Q trunk by
configuring different native VLAN at both ends. Having labbed it, I realize
STP actually blocks off those inconsistent VLANs.

In real-world, I typically set the native VLANs to a bogus non-routable VLAN
and prune it ("switchport trunk allowed vlan remove...") from the trunk.
What's your practice?


Thank you.

B.Rgds,
Lim TS


On 8/24/07, sheherezada@xxxxxxxxx <sheherezada@xxxxxxxxx> wrote:
>
> Yes, you use that when you do dot1q in dot1q (that's it, double
> tagging), so that traffic in the native VLAN can be tunneled
> correctly.
>
> HTH,
>
> Mihai Dumitru
> CCIE #16616 (SP, R&S)
>
> On 8/24/07, Toh Soon, Lim <tohsoon28@xxxxxxxxx> wrote:
> > Hi All,
> >
> > On the other way around, received untagged frames are considered to
> belong
> > to the native VLAN.
> >
> > Does anyone know the practicality of the "vlan dot1q tag native" command
> in
> > the real-world?
> >
> >
> > Thank you.
> >
> > B.Rgds,
> > Lim TS
> >
> >
> > On 8/24/07, Ajay Prakash <ajay.prakash@xxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > In 802.1q encapsulation, there is a native VLAN (Default VLAN 1). The
> > > frames
> > > destined for native VLAN are not tagged by the switch. If you issue
> this
> > > command then all frames including frames for the native VLAN will have
> a
> > > 812.1q header appended.
> > >
> > > Ajay
> > >
> > > -----Original Message-----
> > > From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf
> Of
> > > slevin kremera
> > > Sent: Friday, August 24, 2007 6:49 AM
> > > To: Cisco certification
> > > Subject: vlan dot1q tag native
> > >
> > > whats the use of this command ,what does it accomplish
> > >
> > >
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