RE: Significance of Native Vlan

So it is DTP then. In your setup, what happens if you enable ST on the
interface in question?

Rick

From: S Malik [mailto:ccie.09_at_gmail.com]
Sent: Saturday, November 21, 2009 6:47 PM
To: Rick Darsey
Cc: Cisco certification
Subject: Re: Significance of Native Vlan

Got the answer. Scott Morris explained,

https://learningnetwork.cisco.com/message/40701

On Sat, Nov 21, 2009 at 7:36 PM, S Malik <ccie.09_at_gmail.com> wrote:

I think if ST is enabled and native vlan mismatch is detected then it will
put the port in inconsistant mode (please double check).

On Sat, Nov 21, 2009 at 6:40 PM, Rick Darsey <rdarsey_at_gmail.com> wrote:

I am new here, so if this makes no sense, please excuse it.

I am not clear on the correlation between ST and native VLAN in your
question. Is the Spanning Tree, or DTP?

Rick

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of S
Malik

Sent: Saturday, November 21, 2009 5:09 PM
To: Babatunde Sanda
Cc: Cisco certification
Subject: Re: Significance of Native Vlan

Sanda ,
Thanks for the response. In fact I just wanted to know the significance of
native vlan when "sw mode trunk" and "sw trunk allowed vlan" is configured
and one end has ST disabled on the trunk interface. One end is Cisco and
other end Dell.

I can see trunk forwarding the traffic while interface is in trunking mode
and native vlans on two ends are different.

On Sat, Nov 21, 2009 at 10:55 AM, Babatunde Sanda
<sbabatunde1_at_ca.rr.com>wrote:

> Native vlan is used to carry untagged packets. When you create a vlan the
> number of the vlan becomes the tag and it travels with the packets from
> switch to switch. By default on most vendor switches vlan 1 is the native
> vlan. You can make the native vlan anything you want but you must have
> this
> configuration "SWITCHPORT TRUNK NATIVE VLAN (VLAN NUMBER)" on your trunk
> ports for untagged packets to be carried.
>
> Spanning tree umm! That will require some reading on your part but simply
> put spanning tree is a layer two technology used to prevent loops around
> the
> network. There are different types /modes. Depending on the type of
> spanning tree you have implemented that will determine if you have a
> "blocked port" or "alternate port" status. Either ways you can still
> disable spanning tree on a port (caveat this might prevent loops from
being
> detected on your network). "spanning portfast" can do this on an access
> port. You can also disable it on a trunkport with the spanning tree point
> to point configuration.
>
>
> Spanning tree implementation requires planning on your part and knowing
> your
> network topology well.
>
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of S
> Malik
> Sent: Saturday, November 21, 2009 6:46 AM
> To: Cisco certification
> Subject: Significance of Native Vlan
>
> All,
> If two switches configured for "switchport mode trunk" & " sw trunk encap
> dot1q" and spanning is disabled on one end of the trunk, then what is the
> significance of Native Vlan?
>
>
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>
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Received on Sun Nov 22 2009 - 08:11:05 ART