Double stacked VLANs (was Re: [VLAN] Question on header check)

[ajz at cambridgebroadband.com (Alex Zeffertt)]

>> Another possible problem:  what if you are trying to encapsulate vlan 7 inside
>> of vlan 7.  How do you know to double-encapsulate?  What if user-space is sending
>> a pre-built VLAN frame with a raw socket?  I'm not sure there is enough info as to
>> the intent to encapsulate or not once the VLAN code receives the packet.
> I see how my proposal was wrong. Let me wild guess again :). I wondered if the following
> code could be better. The idea being that the code could determine the need for
> encapsulating or not from the interface's nesting level and the actual number of 
> VLAN tags in the packet.
> 



I think we've had this conversation before.  Search the list archives for "vlan Q in Q"

Alex