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. 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. Neil -- /*************************************************** *Neil Horman *Software Engineer *Red Hat, Inc. *nhorman@xxxxxxxxxx *gpg keyid: 1024D / 0x92A74FA1 *http://pgp.mit.edu ***************************************************/