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* Re: [Bridge] 802.1q packets
@ 2008-07-22 17:40 Fulvio Ricciardi
  2008-07-22 19:35 ` Adam Osuchowski
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-07-22 17:40 UTC (permalink / raw)
  To: Adam Osuchowski, Fulvio Ricciardi; +Cc: bridge


> Fulvio Ricciardi wrote:
> > I notice that with the Kernel 2.6.25.9 the 802.1q VLAN
> > tagged packets larger than 1470 bytes are not forwarded
> > at all by a bridge.
> > I think there is a bad interaction between bridge and
> > netfilter codes. Any chance to a have a patch to solve
> > this problem that limit the possibility to use the Linux
> > bridges in a environment with VLANs?
> 
> Is it maybe problem described here?
> 
>  
>
https://lists.linux-foundation.org/pipermail/bridge/2007-May/005436.html
> 
> If so, it was reported more than one year ago and still
> none of developers care about it.
> 

Yes, it is exactly the same problem. Thanks for the patch
that I hope developers will include it in the vanilla Kernel
as soon as possible.

Regards 
Fulvio Ricciardi


--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-30 17:07 Fulvio Ricciardi
  2008-06-30 22:42 ` richardvoigt
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-30 17:07 UTC (permalink / raw)
  To: richardvoigt@gmail.com; +Cc: Stephen Hemminger, bridge


> 
> That mostly rules out other devices in the path as the
> cause of the problem.  There's just one chance of a
> netfilter interaction that I can think of: netfilter may
> cause fragments to be recombined, without netfilter the
> fragments could be bridged.  Are you running the ping
> command from the bridge itself, or across the bridge? (I
> presume across the bridge because you are discussing the
> FORWARD chain only)

I ping across the bridge. If instead a ping from the bridge
itself, all works right.

> 
> Do the large ping requests show up in the iptables
> counters?

Yes, in any case (either ping -s 1472 and ping -s 1473) the
packets are counted in the FORWARD chain.

> 
> What happens if you set no fragmentation when you run
> ping?

it's the same

Thanks
Fulvio

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-30 16:58 Fulvio Ricciardi
  0 siblings, 0 replies; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-30 16:58 UTC (permalink / raw)
  To: Leigh Sharpe, Fulvio Ricciardi, bridge


> I had a similar problem not long ago. Make sure that
> ip_conntrack is not loaded. In my case, it was
> re-assembling all fragmented packets passing through the
> bridge, and not fragmenting them again. The resulting
> large packet was too big for the interface, and it got
> dropped. 
> 

I use the modules nf_conntrack_ipv4 and nf_conntrack. I
can't remove them. Does exist a workaround if this is the
problem?

Thanks
Fulvio 

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-30  5:53 Leigh Sharpe
  0 siblings, 0 replies; 20+ messages in thread
From: Leigh Sharpe @ 2008-06-30  5:53 UTC (permalink / raw)
  To: Fulvio Ricciardi, bridge

I had a similar problem not long ago. Make sure that ip_conntrack is not
loaded. In my case, it was re-assembling all fragmented packets passing
through the bridge, and not fragmenting them again. The resulting large
packet was too big for the interface, and it got dropped. 

Regards,
             Leigh
 
Leigh Sharpe
Network Systems Engineer
Pacific Wireless
Ph +61 3 9584 8966
Mob 0408 009 502
Helpdesk 1300 300 616
email lsharpe@pacificwireless.com.au
web www.pacificwireless.com.au
 

-----Original Message-----
From: bridge-bounces@lists.linux-foundation.org
[mailto:bridge-bounces@lists.linux-foundation.org] On Behalf Of Fulvio
Ricciardi
Sent: Saturday, 28 June 2008 2:56 PM
To: bridge@osdl.org
Subject: [Bridge] 802.1q packets

Hi,

I notice that with the Kernel 2.6.25.9 the 802.1q VLAN
tagged packets larger than 1470 bytes are not forwarded at
all by a bridge.
I think there is a bad interaction between bridge and
netfilter codes. Any chance to a have a patch to solve this
problem that limit the possibility to use the Linux bridges
in a environment with VLANs?

Best Regards
Fulvio Ricciardi

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630
_______________________________________________
Bridge mailing list
Bridge@lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/bridge

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-28 21:17 Fulvio Ricciardi
  2008-06-29  0:08 ` richardvoigt
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-28 21:17 UTC (permalink / raw)
  To: richardvoigt@gmail.com, Fulvio Ricciardi; +Cc: Stephen Hemminger, bridge


> > > > > Hi,
> > > > >
> > > > > I notice that with the Kernel 2.6.25.9 the 802.1q
> > > > > VLAN tagged packets larger than 1470 bytes are not
> > > > > forwarded at all by a bridge.
> > > > > I think there is a bad interaction between bridge
> > > > > and netfilter codes. Any chance to a have a patch
> > > > > to solve this problem that limit the possibility
> > > > > to use the Linux bridges in a environment with
> > > VLANs? >
> > > > With the following command it works:
> > > >
> > > > echo 0 >
> > > /proc/sys/net/bridge/bridge-nf-call-iptables >
> > > > but this disable the iptables support that it's
> > > > important for obtaining complex bridge-firewall
> > > > scenarios.
> > > > Regards
> > > > Fulvio Ricciardi
> > >
> > > Your iptables need to know about VLAN's as well.
> > > I bet your default action is to DROP.
> > >
> > No, the default policy is ACCEPT for the FORWARD chain.
> > In any case the problem takes place only with large
> > packets. For example if I try
> >
> > ping -s 1472 192.168.99.74
> >
> > it works, but
> >
> > ping -s 1473 192.168.99.74
> >
> > it does not.
> > I am sure that the network cards are VLAN 802.1q aware
> > because only the forwarding process is broken. If
> > instead I just ping the IP of the bridge interface it
> works fine.
> 
> 
> Are the other nodes directly connected to the netfilter
> bridge, or are there ethernet switches involved?   Are
> these switches managed, smart, or dumb? Are jumbo frames
> enabled on all devices in the path?
> 


One host is directly connected with a cross cable to the
bridge and the other one with an unmanaged switch that works
fine because if I issue the command

echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables

to disable the Netfilter action for the bridge there is no
problem for the large packets on VLAN.



--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-28 19:50 Fulvio Ricciardi
  2008-06-28 21:06 ` richardvoigt
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-28 19:50 UTC (permalink / raw)
  To: Stephen Hemminger, Fulvio Ricciardi; +Cc: bridge


> > > Hi,
> > > 
> > > I notice that with the Kernel 2.6.25.9 the 802.1q VLAN
> > > tagged packets larger than 1470 bytes are not
> > > forwarded at all by a bridge.
> > > I think there is a bad interaction between bridge and
> > > netfilter codes. Any chance to a have a patch to solve
> > > this problem that limit the possibility to use the
> > > Linux bridges in a environment with VLANs?
> > 
> > With the following command it works:
> > 
> > echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables
> > 
> > but this disable the iptables support that it's
> > important for obtaining complex bridge-firewall
> > scenarios. 
> > Regards
> > Fulvio Ricciardi
> 
> Your iptables need to know about VLAN's as well.
> I bet your default action is to DROP.
> 
No, the default policy is ACCEPT for the FORWARD chain. In
any case the problem takes place only with large packets.
For example if I try

ping -s 1472 192.168.99.74

it works, but

ping -s 1473 192.168.99.74

it does not.
I am sure that the network cards are VLAN 802.1q aware
because only the forwarding process is broken. If instead I
just ping the IP of the bridge interface it works fine.

Regards
Fulvio

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* Re: [Bridge] 802.1q packets
@ 2008-06-28 12:07 Fulvio Ricciardi
  2008-06-28 18:31 ` Stephen Hemminger
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-28 12:07 UTC (permalink / raw)
  To: bridge


> Hi,
> 
> I notice that with the Kernel 2.6.25.9 the 802.1q VLAN
> tagged packets larger than 1470 bytes are not forwarded at
> all by a bridge.
> I think there is a bad interaction between bridge and
> netfilter codes. Any chance to a have a patch to solve
> this problem that limit the possibility to use the Linux
> bridges in a environment with VLANs?

With the following command it works:

echo 0 > /proc/sys/net/bridge/bridge-nf-call-iptables

but this disable the iptables support that it's important
for obtaining complex bridge-firewall scenarios.

Regards
Fulvio Ricciardi

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread
* [Bridge] 802.1q packets
@ 2008-06-28  4:56 Fulvio Ricciardi
  2008-07-22 11:09 ` Adam Osuchowski
  0 siblings, 1 reply; 20+ messages in thread
From: Fulvio Ricciardi @ 2008-06-28  4:56 UTC (permalink / raw)
  To: bridge

Hi,

I notice that with the Kernel 2.6.25.9 the 802.1q VLAN
tagged packets larger than 1470 bytes are not forwarded at
all by a bridge.
I think there is a bad interaction between bridge and
netfilter codes. Any chance to a have a patch to solve this
problem that limit the possibility to use the Linux bridges
in a environment with VLANs?

Best Regards
Fulvio Ricciardi

--------------------------------------------------------------------
Fulvio Ricciardi
web: http://www.zeroshell.net/eng/
skype: zeroshellnet
Phone: +3908321835630

^ permalink raw reply	[flat|nested] 20+ messages in thread

end of thread, other threads:[~2009-03-17 16:26 UTC | newest]

Thread overview: 20+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-07-22 17:40 [Bridge] 802.1q packets Fulvio Ricciardi
2008-07-22 19:35 ` Adam Osuchowski
2008-07-22 21:59   ` Stephen Hemminger
2008-07-23  3:51     ` richardvoigt
2008-09-20 20:47     ` Adam Osuchowski
  -- strict thread matches above, loose matches on Subject: below --
2008-06-30 17:07 Fulvio Ricciardi
2008-06-30 22:42 ` richardvoigt
2008-07-01 15:10   ` Patrick McHardy
2009-03-17 14:58     ` Saikiran Madugula
2009-03-17 16:26       ` Saikiran Madugula
2008-06-30 16:58 Fulvio Ricciardi
2008-06-30  5:53 Leigh Sharpe
2008-06-28 21:17 Fulvio Ricciardi
2008-06-29  0:08 ` richardvoigt
2008-06-28 19:50 Fulvio Ricciardi
2008-06-28 21:06 ` richardvoigt
2008-06-28 12:07 Fulvio Ricciardi
2008-06-28 18:31 ` Stephen Hemminger
2008-06-28  4:56 Fulvio Ricciardi
2008-07-22 11:09 ` Adam Osuchowski

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