RE: When to do the QinQ

Hi Jules!

Great job seeing that the tunneling of Layer 2 traffic like CDP and STP is
independent from QinQ tunneling of traffic. While the two often are used
together, they certainly do not have to be. In the actual exam you will just
want to read very carefully to see which of the two features (or both) are
required. One clue will certainly be in what you are needing to connect as
you pointed out. Another important thing to watch for is if the VLAN
infrastructure is rigidly spelled out, or if you have flexibility in the
creation of additional VLANs.

Warmest regards,

Anthony Sequeira, CCIE, CCSI
StormWind's Epic Live
http://www.stormwindlive.com

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
jules NYA BAWEU
Sent: Thursday, February 24, 2011 5:16 PM
To: Cisco certification
Subject: When to do the QinQ

Hello all,

I have seen numerous tasks in R&S workbooks with regard to L2 Tunneling
being answered with automatic QinQ config at point exit/entrance of the
tunnel.

==========================
system mty 1504

int gi1/0/x
switch access vlan Y
switch mode dot1q-tunnel
l2protocol-tunnel cdp
l2protocol-tunnel stp

int gi1/0/w
switch access vlan Y
switch mode dot1q-tunnel
l2protocol-tunnel cdp
l2protocol-tunnel stp
==========================

Shouldn't the first task being to identify what is going to be connected at
the entry point of the tunnel?

let's say it is a L3 interface, then there is not need for the QinQ to bring
up the tunnel.

the above will then translate to:
==========================
int gi1/0/x
switch access vlan Y
switch mode access
l2protocol-tunnel cdp
l2protocol-tunnel stp

int gi1/0/w
switch access vlan Y
switch mode access
l2protocol-tunnel cdp
l2protocol-tunnel stp
==========================

--> Now if effectively a L2 trunk is going to be connected, then the QinQ.

Should I just see this type of question like "just make sure anything the
customer connect at entry point of the tunnel should go through?"

Thanks in advance

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Received on Sat Feb 26 2011 - 15:30:30 ART