VLANs and bridge

VLANs and bridge

[Joakim Tjernlund]

This is probably no news to experienced bridge and VLAN users but I just learned the
hard way that Shared VLAN learning(SVL) isn't supported
by the linux bridge making it impossible to support configurations described in B.1.3
Basically the bride needs to be made VLAN aware and the VLAN code needs to be adopted
to allow this.

I figured I should mention it in case it is just an oversight. It does not look like a simple
job though.

 Jocke

Re: VLANs and bridge

[Simon Barber]

Hi Joakim,

Look back a month or so in the archives - you'll find an email from me 
referencing a patch to make the bridge VLAN aware. It's a little old, 
and needs updating for 2.6 (it was written for 2.4) - but should not be 
much work to get it done. There is a matching patch for the brctl utility.

Simon


Joakim Tjernlund wrote:
> This is probably no news to experienced bridge and VLAN users but I just learned the
> hard way that Shared VLAN learning(SVL) isn't supported
> by the linux bridge making it impossible to support configurations described in B.1.3
> Basically the bride needs to be made VLAN aware and the VLAN code needs to be adopted
> to allow this.
>
> I figured I should mention it in case it is just an oversight. It does not look like a simple
> job though.
>
>  Jocke
>
> _______________________________________________
> Bridge mailing list
> Bridge@lists.linux-foundation.org
> https://lists.linux-foundation.org/mailman/listinfo/bridge
>   

Re: [Bridge] VLANs and bridge

[Joakim Tjernlund]

Simon Barber <simon@superduper.net> wrote on 22/08/2009 16:34:11:
>
> Hi Joakim,
>
> Look back a month or so in the archives - you'll find an email from me
> referencing a patch to make the bridge VLAN aware. It's a little old,
> and needs updating for 2.6 (it was written for 2.4) - but should not be
> much work to get it done. There is a matching patch for the brctl utility.
>
> Simon
>

Thanks Simon

Do you mean the "bridge vlan integration" patch?
It is not clear to me if this would support the case
described in B.1.3(802.1Q-2005), does it?

Seems like there is little interest to post this to 2.6 and
I am not sure how welcome this would be either, perhaps
the bridge maintainer could comment?

  Jocke

>
> Joakim Tjernlund wrote:
> > This is probably no news to experienced bridge and VLAN users but I just learned the
> > hard way that Shared VLAN learning(SVL) isn't supported
> > by the linux bridge making it impossible to support configurations described in B.1.3
> > Basically the bride needs to be made VLAN aware and the VLAN code needs to be adopted
> > to allow this.
> >
> > I figured I should mention it in case it is just an oversight. It does not
> look like a simple
> > job though.
> >
> >  Jocke
> >
> > _______________________________________________
> > Bridge mailing list
> > Bridge@lists.linux-foundation.org
> > https://lists.linux-foundation.org/mailman/listinfo/bridge
> >
>
>
>

Re: [Bridge] VLANs and bridge

[Joakim Tjernlund]

Joakim Tjernlund/Transmode wrote on 22/08/2009 17:36:54:
>
> Simon Barber <simon@superduper.net> wrote on 22/08/2009 16:34:11:
> >
> > Hi Joakim,
> >
> > Look back a month or so in the archives - you'll find an email from me
> > referencing a patch to make the bridge VLAN aware. It's a little old,
> > and needs updating for 2.6 (it was written for 2.4) - but should not be
> > much work to get it done. There is a matching patch for the brctl utility.
> >
> > Simon
> >
>
> Thanks Simon
>
> Do you mean the "bridge vlan integration" patch?
> It is not clear to me if this would support the case
> described in B.1.3(802.1Q-2005), does it?
>
> Seems like there is little interest to post this to 2.6 and
> I am not sure how welcome this would be either, perhaps
> the bridge maintainer could comment?
>
>   Jocke

Thinking a bit more about this I could envision some changes to the
vlan code too. I image one could create one vlan interface which will listen
to several VLANs. One VLAN is the primary VLAN and is used in the tx path
by default. The bridge would be able to filter on individual VLANs received
from such interface and be able to chose outgoing VLAN too.

 Jocke

Re: [Bridge] VLANs and bridge

[Simon Barber]

Looking through B.1.3 it looks like the patch would need some 
enhancement. It provides a good basis - handling tagging/untagging and 
filtering, but would need a way to specify the untagged vlan separately 
for in and out.

Simon


Joakim Tjernlund wrote:
> Joakim Tjernlund/Transmode wrote on 22/08/2009 17:36:54:
>   
>> Simon Barber <simon@superduper.net> wrote on 22/08/2009 16:34:11:
>>     
>>> Hi Joakim,
>>>
>>> Look back a month or so in the archives - you'll find an email from me
>>> referencing a patch to make the bridge VLAN aware. It's a little old,
>>> and needs updating for 2.6 (it was written for 2.4) - but should not be
>>> much work to get it done. There is a matching patch for the brctl utility.
>>>
>>> Simon
>>>
>>>       
>> Thanks Simon
>>
>> Do you mean the "bridge vlan integration" patch?
>> It is not clear to me if this would support the case
>> described in B.1.3(802.1Q-2005), does it?
>>
>> Seems like there is little interest to post this to 2.6 and
>> I am not sure how welcome this would be either, perhaps
>> the bridge maintainer could comment?
>>
>>   Jocke
>>     
>
> Thinking a bit more about this I could envision some changes to the
> vlan code too. I image one could create one vlan interface which will listen
> to several VLANs. One VLAN is the primary VLAN and is used in the tx path
> by default. The bridge would be able to filter on individual VLANs received
> from such interface and be able to chose outgoing VLAN too.
>
>  Jocke
>
>   

Re: [Bridge] VLANs and bridge

[Joakim Tjernlund]

Simon Barber <simon@superduper.net> wrote on 22/08/2009 19:12:10:
>
> Looking through B.1.3 it looks like the patch would need some
> enhancement. It provides a good basis - handling tagging/untagging and
> filtering, but would need a way to specify the untagged vlan separately
> for in and out.

I see. Perhaps the VLAN maintainer(CC:ed) can comment too. Especially about extending
the VLAN code to allowed several VLANs in one interface?

>
> Simon
>
>
> Joakim Tjernlund wrote:
> > Joakim Tjernlund/Transmode wrote on 22/08/2009 17:36:54:
> >
> >> Simon Barber <simon@superduper.net> wrote on 22/08/2009 16:34:11:
> >>
> >>> Hi Joakim,
> >>>
> >>> Look back a month or so in the archives - you'll find an email from me
> >>> referencing a patch to make the bridge VLAN aware. It's a little old,
> >>> and needs updating for 2.6 (it was written for 2.4) - but should not be
> >>> much work to get it done. There is a matching patch for the brctl utility.
> >>>
> >>> Simon
> >>>
> >>>
> >> Thanks Simon
> >>
> >> Do you mean the "bridge vlan integration" patch?
> >> It is not clear to me if this would support the case
> >> described in B.1.3(802.1Q-2005), does it?
> >>
> >> Seems like there is little interest to post this to 2.6 and
> >> I am not sure how welcome this would be either, perhaps
> >> the bridge maintainer could comment?
> >>
> >>   Jocke
> >>
> >
> > Thinking a bit more about this I could envision some changes to the
> > vlan code too. I image one could create one vlan interface which will listen
> > to several VLANs. One VLAN is the primary VLAN and is used in the tx path
> > by default. The bridge would be able to filter on individual VLANs received
> > from such interface and be able to chose outgoing VLAN too.
> >
> >  Jocke
> >
> >
>
>
>

Re: [Bridge] VLANs and bridge

[Patrick McHardy]

Joakim Tjernlund wrote:
> Simon Barber <simon@superduper.net> wrote on 22/08/2009 19:12:10:
>> Looking through B.1.3 it looks like the patch would need some
>> enhancement. It provides a good basis - handling tagging/untagging and
>> filtering, but would need a way to specify the untagged vlan separately
>> for in and out.
> 
> I see. Perhaps the VLAN maintainer(CC:ed) can comment too. Especially about extending
> the VLAN code to allowed several VLANs in one interface?

Just accepting additional VIDs on one VLAN device should be
a relatively trivial change, all you need to do is call
vlan_group_set_device() with the additional VIDs.

I'd suggest to add something similar to the QoS-mapping lists
in vlan_netlink.c for the additional VIDs.

Re: [Bridge] VLANs and bridge

[Joakim Tjernlund]

Patrick McHardy <kaber@trash.net> wrote on 25/08/2009 16:00:44:
>
> Joakim Tjernlund wrote:
> > Simon Barber <simon@superduper.net> wrote on 22/08/2009 19:12:10:
> >> Looking through B.1.3 it looks like the patch would need some
> >> enhancement. It provides a good basis - handling tagging/untagging and
> >> filtering, but would need a way to specify the untagged vlan separately
> >> for in and out.
> >
> > I see. Perhaps the VLAN maintainer(CC:ed) can comment too. Especially about extending
> > the VLAN code to allowed several VLANs in one interface?
>
> Just accepting additional VIDs on one VLAN device should be
> a relatively trivial change, all you need to do is call
> vlan_group_set_device() with the additional VIDs.
>
> I'd suggest to add something similar to the QoS-mapping lists
> in vlan_netlink.c for the additional VIDs.

Yes, this seems to be the easy part. There are a few bride issues though:
How would the bridge be able to filter pks based on VID?
How to control which VID to use at pkg TX?
Can you have the same VID on multiple VLAN interfaces?

     Jocke