Bridging two vlans on a single interface don't work (kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 )

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>Today's Topics:
>
>   1. Re: Bridging two vlans on a single interface don't work (
>      kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 )
>      (Alvin Starr)
>   2. Bridging two vlans on a single interface don't work (
>      kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 ) (a.gatta)
>   3. Re: Bridging two vlans on a single interface don't work (
>      kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 )
>      (Ard van Breemen)
>   4. Re: QoS, setting skb->priority (Alex Zeffertt)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Wed, 03 May 2006 22:28:43 -0400
>From: Alvin Starr <[email protected]>
>Subject: Re: [VLAN] Bridging two vlans on a single interface don't
>	work ( kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 )
>To: "Linux 802.1Q VLAN" <[email protected]>
>Message-ID: <[email protected]>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>The problem you may be running into could be caused by the switches 
>broadcasting spanning tree packets. These will be broadcast back to the 
>switch causing some confusion.
>take a look at
>http://lists.osdl.org/pipermail/bridge/2005-October/001116.html
>
>a.gatta wrote:
>
>  
>
>>Dear List,
>>I am experiencing problems bridging two vlans on a linux box running 
>>debian.
>>
>>I have a single interface (eth0,Broadcom NetXtreme BCM5705M_2 with tg3 
>>module).
>>
>>This interface has a trunk to a catalyst switch.
>>
>>
>>I've created two virtual interface with vconfig:
>>
>>vconfig add eth0 608
>>vconfig add eth0 609
>>
>>At this point all is fully functional, I am able to see traffic on 
>>those virtual interfaces and if I give them the ip stack I can use them.
>>
>>Then I decided two bridge the two virtual interfaces.
>>
>>So I created a bridge with brctl :
>>
>>brctl addbr br0
>>
>>and I've added those virtual interfaces to the bridge :
>>
>>brctl addif br0 eth0.608
>>brctl addif br0 eth0.609
>>
>>Last thing I enable all the interfaces :
>>
>>ifconfig br0 up
>>ifconfig eth0.608 up
>>ifconfig eth0.609 up
>>
>>The first thing I noticed is that I cannot see any traffic on br0 
>>interface and also on the virtual interfaces.
>>
>>As far as I know the bridge code supports tagged packet but I am not 
>>able to see any traffic on the interfaces.
>>
>>Moreover the tg3 module support natively vlan traffic.
>>
>>This is what I see on both br0 and virtual interfaces after I add them 
>>to the bridge :
>>
>>14:23:22.539413 00:0a:b7:23:61:97 > 01:00:0c:cc:cc:cd SNAP Unnumbered, 
>>ui, Flags [Command], length 50
>>14:23:22.540865 00:0a:b7:23:61:97 > 01:00:0c:cc:cc:cd SNAP Unnumbered, 
>>ui, Flags [Command], length 50
>>
>>Any ideas ?
>>
>>    
>>
>
>
>  
>
Alvin,
you are right.

The link you've submitted is really clear.

The stp implementation running on the linux box does not understand 
PVST+ and then the multicast traffic
is bridged back to the cisco that originate it.

Cheers