From: Ravi Singh (way2ccie@googlemail.com)
Date: Sun Mar 08 2009 - 05:41:00 ARST
Hi Group,
I have a very small but quite significant doubt on the use of Native Vlan in
a Dot1q tunnel. If you check Cisco's documentation for Dot1q tunnel and go
to the section Native vlan , specifically to this URL (mind the word wrap
please)
The document says "Switch A of Customer X sends a tagged packet on VLAN 30
to the ingress tunnel port of Switch B in the service-provider network,
which belongs to access VLAN 40. Because the access VLAN of the tunnel port
(VLAN 40) is the same as the native VLAN of the edge-switch trunk port (VLAN
40), the metro tag is not added to tagged packets received from the tunnel
port".
My confusion is , if the packet(rather frame) comes tagged with VLAN 30,
shouldn't the provider Switch B tag it with its metro tag, since this was a
tagged frame with a non-native VLAN and not an untagged/Native VLAN frame. I
think, If the frame is sourced from VLAN 40 , the native VLAN, it should be
then that Switch B shouldn't tag it because its access VLAN on the tunnel
port is the same as the VLAN on the untagged frame.
Any input is appreciated.
TIA,
Ravi
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Mon Apr 06 2009 - 06:44:04 ART