On Fri, 2007-21-09 at 14:50 +0200, Emil Micek wrote: > On Fri, 2007-09-21 at 07:59 -0400, jamal wrote:
> > Which would make it a bug. AFAIK, the minimum VLAN tagged packet going > > out is 68 bytes. > Are you sure about this? This is what i have always seen. Double checked with google and she gave me many a url, example: http://www.cisco.com/warp/public/473/741_4.html I think you can pretty much trust cisco on something as basic as this. Also: http://www.techfest.com/networking/lan/ethernet2.htm > We did some extensive testing capturing VLAN > frames going out of our Intel PRO/1000 MT Dual Port Server Adapter > (82571EB chipset) and we definitely captured VLAN frames shorter then 68 > bytes. Here is text dump of such frame: > http://www.tkrjasek.cz/mie/cmts_tests/between_linux_and_cmts.txt Do you have access to another NIC? a tg3 based one will be good to test for hardware level tagging. > (note that wireshark captures the frames without 4 bytes FCS (frame > check sequence) so the above packet is in fact 66 bytes long). > > What is the right behaviour according to specification? In iee802.3, > minFrameSize is 64bytes. I've never seen any document which'd say that > VLAN frames should be 68 bytes minimum. Refer to above. > Now i'm little confused by your reply, becaouse you write, that VLAN > frames generated by e1000 should be 68 bytes minimum, which contradicts > witch our observations. Miscommunication ;-> I said the packets going out should be 68B otherwise it is a bug. if e1000 is sending 64B out, it is a bug. I think any other NIC that doesnt do hardware based vlan tags would be good to try as well because it uses the software stack to do the tagging. cheers, jamal - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
