On Fri, Feb 15, 2019 at 12:27:11AM +0100, Matthias May wrote: > On 14/02/2019 20:17, Ben Pfaff wrote: > > On Thu, Feb 14, 2019 at 10:58:48AM +0100, Matthias May via dev wrote: > >> There are switches which allow to transmit their BPDUs VLAN-tagged. > >> With this change OVS is able to receive VLAN-tagged BPDUs, but still > >> transmits its own BPDUs untagged. > >> This was tested against Westermo RFI-207-F4G-T3G. > >> > >> Signed-off-by: Matthias May <matthias....@neratec.com> > > > > Thanks for the patch. > > > > To me, it seems really odd to treat packets with and without an > > arbitrary VLAN header the same way. I could see it if the VLAN header > > had VID 0 or 1 or some other specified value, but it seems unusual to > > ignore it entirely. Is this standardized or a de facto standard of some > > kind? > > > > I totally agree. > To me a VLAN header has nothing lost on a BPDU of a (R)STP frame, simply > because (R)STP is not per VLAN. > > However the fact is that there are switches which are transmitting > frames on a VLAN. > > With this change we simply ignore the VLAN header if is present. The > meaning of the BPDU doesn't cheange. The provided information still is > not per VLAN and applies to all ports the same. > > This patch does not add the ability to transmit VLAN tagged BPDUs for > the same reasoning above: RSTP/STP is not supposed to be per VLAN. > I was thinking about adding to the patch that one can specify a VLAN via > config and only BPDUs with the configured VLAN are accepted. I guess > this is what you propose: only accept vlan tagged BPDUs on a specified VLAN. > Having such a config-parameter would also enable to transmit the BPDUs > VLAN tagged. But I'm still of the opinion that this only suggests that > one could have an (R)STP tree per VLAN.
I see we are basically in agreement, but I'd like more information, if you have it. Do the switches that transmit RSTP on a VLAN transmit it on a particular VLAN like 0 or 1? (Maybe they are transmitting them as priority-tagged frames for some reason?) If so, then it would be possible to accept just that VLAN. _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
