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

Thu May 4 14:47:48 PDT 2006

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>Today's Topics:
>
>   1. Bridging two vlans on a single interface don't work (
>      kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 ) 
>      (a.gatta)
>   2. Re: Bridging two vlans on a single interface don't work (
>      kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 )
>      (Roy-Magne Mo)
>   3. Re: Two VLANs with same IP (Rui Cristo)
>   4. QoS, setting skb->priority (Rui Cristo)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Wed, 03 May 2006 14:24:58 +0200
>From: "a.gatta" <a.gatta at tiscali.it>
>Subject: [VLAN] Bridging two vlans on a single interface don't work (
>	kernel2.6.15, tg3 driver for Broadcom NetXtreme BCM5705M_2 ) 
>To: vlan at candelatech.com
>Message-ID: <4458A11A.8070009 at tiscali.it>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>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 ?
>
>
>
>
>
>
>cisco
>
>------------------------------
>
>Message: 2
>Date: Wed, 03 May 2006 17:44:11 +0200
>From: Roy-Magne Mo <rmo at sunnmore.net>
>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" <vlan at candelatech.com>
>Message-ID: <1146671052.29212.3.camel at localhost.localdomain>
>Content-Type: text/plain
>
>on den 03.05.2006 klokka 14:24 (+0200) skreiv a.gatta:
>  
>
>>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 ?
>>    
>>
>
>
>Do you see the mac address of your switch on both of these vlans on the
>cisco switch? A lot of (broken) switches will croak on traffic flowing
>this way. 
>
>
>
>
>
>------------------------------
>
>Message: 3
>Date: Wed, 3 May 2006 13:46:11 -0300 (ART)
>From: Rui Cristo <rui_alisson at yahoo.com.br>
>Subject: Re: [VLAN] Two VLANs with same IP
>To: "Linux 802.1Q VLAN" <vlan at candelatech.com>
>Message-ID: <20060503164611.44820.qmail at web42407.mail.yahoo.com>
>Content-Type: text/plain; charset="iso-8859-1"
>
>The problem was solved using SO_BINDTODEVICE to both VLANs, thanks.
>  
>Ben Greear <greearb at candelatech.com> escreveu:
>  Ard van Breemen wrote:
>  
>
>>On Tue, May 02, 2006 at 11:06:49AM -0300, Rui Cristo wrote:
>>
>>    
>>
>>>I have a problem to solve that is to create two VLANs, like
>>>vlan10 and vlan20, and make them have the SAME IP address and I
>>>want to create sockets for each. How can I bind the sockets to
>>>each VLAN instead of binding them to its IP? If I bind with
>>>it's IP I can't control wich VLAN to choose.
>>>      
>>>
>>IP binding is done on a system level. So it really doesn't matter
>>if your IP is on lo or vlan*...
>>    
>>
>
>You can actually tweak this by using policy-based routing and binding
>to local IP and/or devices with sock-opts, and messing with the
>/proc/sys/net/arp filter logic..but it takes a bit of work.
>
>Ben
>
>  
>
Dear list,
I found the problem.

The switch puts in blocking state the two vlan :

3w0d: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer 
vlan id 608 on FastEthernet0/23 VLAN609.
3w0d: %SPANTREE-2-BLOCK_PVID_PEER: Blocking FastEthernet0/23 on 
VLAN0608. Inconsistent peer vlan.
3w0d: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking FastEthernet0/23 on 
VLAN0609. Inconsistent local vlan

sh spanning-tree int fastEthernet 0/23
....

VLAN0608         Desg BKN*19        128.23   P2p *PVID_Inc
VLAN0609         Desg BKN*19        128.23   P2p *PVID_Inc
....

This is due to the interaction between PVST+ and CST ( on linux bridge ).

This is the configuration on linux bridge :

host:/proc/net/vlan# brctl show
bridge name     bridge id               STP enabled     interfaces
br0             8000.000802e842b7       yes                    eth0.609

eth0.608

The int fast 0/23 is a dot1q trunk with native vlan 1.

It there any way to overcome this issue other than disable spanning tree 
on the switch port ?

Regards