Linux Ethernet Bridging - Oct 2018 - [Bridge] [PATCH 1/1] bridge: remove BR_GROUPFWD_RESTRICTED for arbitrary forwarding of reserved addresses

On Mon, Oct 01, 2018 at 08:16:22PM +0200, Richard Weinberger
wrote:
> Florian,
> 
> Am Montag, 1. Oktober 2018, 18:24:25 CEST schrieb Florian Fainelli:
> > If all you are doing is forwarding anything, one thing I experimented
> > with before is the following:
> > 
> > # tc qdisc add dev eth1 handle ffff: ingress
> > # tc qdisc add dev eth3 handle ffff: ingress
> > # tc filter add dev eth3 parent ffff: u32 \
> > > match u32 0 0 \
> > > action mirred egress redirect dev eth1
> > # tc filter add dev eth1 parent ffff: u32 \
> > > match u32 0 0 \
> > > action mirred egress redirect dev eth3
> > # ifconfig eth3 promisc
> > # ifconfig eth1 promisc
> > 
> > and this works just fine actually, bypassing the bridge layer
entirely.
> 
> Yeah, mirred is a powerful knife. :-)
> 
> In my case it is too low level since I utilize the netfilter functionality
of
> the bridge layer.
You can use mirred only for the specific packets you care about and let
the rest continue to the bridge.

Am Montag, 1. Oktober 2018, 20:25:26 CEST schrieb Ido
Schimmel:
> On Mon, Oct 01, 2018 at 08:16:22PM +0200, Richard Weinberger wrote:
> > Florian,
> > 
> > Am Montag, 1. Oktober 2018, 18:24:25 CEST schrieb Florian Fainelli:
> > > If all you are doing is forwarding anything, one thing I
experimented
> > > with before is the following:
> > > 
> > > # tc qdisc add dev eth1 handle ffff: ingress
> > > # tc qdisc add dev eth3 handle ffff: ingress
> > > # tc filter add dev eth3 parent ffff: u32 \
> > > > match u32 0 0 \
> > > > action mirred egress redirect dev eth1
> > > # tc filter add dev eth1 parent ffff: u32 \
> > > > match u32 0 0 \
> > > > action mirred egress redirect dev eth3
> > > # ifconfig eth3 promisc
> > > # ifconfig eth1 promisc
> > > 
> > > and this works just fine actually, bypassing the bridge layer
entirely.
> > 
> > Yeah, mirred is a powerful knife. :-)
> > 
> > In my case it is too low level since I utilize the netfilter
functionality of
> > the bridge layer.
> 
> You can use mirred only for the specific packets you care about and let
> the rest continue to the bridge.
This is my plan b, having a u32 classifier that transports STP directly
to the other interface.
But IMHO this all is a bit hacky and a "forward anything" bridge mode
sounds more natural to me.

Thanks,
//richard