On Mon, Jan 10, 2005 at 02:41:34PM -0500, Neil Horman wrote: > Gergely Madarasz wrote: > >On Mon, Jan 10, 2005 at 12:40:57PM -0500, Neil Horman wrote: > > > >>Gergely Madarasz wrote: > >> > >>>On Mon, Jan 10, 2005 at 11:04:55AM -0500, Neil Horman wrote: > >>> > >>> > >>>>Strange. My concern was that the tg3 interface has its hardware reset > >>>>whenever its set to be up, and part of that is a resetting of its > >>>>receive mode. If for some reason IFF_PROMISC was cleared after you set > >>>>it using brctl, the interface might be taken out of promisc mode. Do > >>>>you have any iptables rules running that might drop bpdus? > >>> > >>> > >>>No iptables rules az all. Btw iptables wouldn't prevent tcpdump from > >>>seeing the packets, would it? > >>>Could it be that the driver perhaps has a problem setting promisc mode > >>>when resetting the hardware? > >>> > >> > >>Not really sure about this. One experiment is worth a thousand guesses > >>I suppose....... I'll try and let you know. :) > > > > > >I did some other checks, like adding an explicit ifconfig eth0 promisc, > >then looking at tcpdump output - I didn't see any stray packets like I > >usually do, just ethernet broadcasts and unicasts to my mac, this also > >points to a problem that the ethernet interface is actually not in > >promisc, while the driver thinks it is. > > > >And it is probably not a driver-only issue. I've got older machines with > >tg3 running fine with bridge (with an older tg3 driver), and eth1 on the > >same machine also runs fine. On another machine I tested today, an IBM > >x326, the same thing happens - eth0 broken, eth1 fine. Would access to one > >of these machines help? :) > > > >Greg > I've got a tg3 card here. I'll try re-create it as soon as I have time. Sounds great, but I expect it will not occur with a random tg3 card, explained above... > Just out of curiosity, are you running tcpdump against the physical > interface or the bridged interface? I do recall some issues involving > using PF_PACKET on virtual interfaces, that might cause you to not see > some packets that the physical interface really does receive. The physical interface of course. I wouldn't have a chance seeing the bpdu's on the bridge interface because they're handled by the bridge driver and not passed on :) Greg - : send the line "unsubscribe linux-net" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
