Re: [dpdk-dev] Issue with pktgen-dpdk replaying >1500bytes pcap on MCX4

[Damien Clabaut <damien.clabaut@corp.ovh.com>]

Hello and thank you for your answer,

We use the following versions:

MLNX DPDK version 16.11, revision 3.0

pktgen-dpdk version 3.3.8

mlnx_ofed version 4.1-1.0.2.0

fw revision: 12.18.1000

Regards,


On 2017-09-25 08:46 PM, Yongseok Koh wrote:
> Hi, Damien
>
> Can you please let me know the versions of your SW - pktgen-dpdk, DPDK and MLNX_OFED?
> Also Firmware version if available.
>
> Thanks,
> Yongseok
>
>> On Sep 25, 2017, at 10:19 AM, Damien Clabaut <damien.clabaut@corp.ovh.com> wrote:
>>
>> Hello DPDK devs,
>>
>> I am sending this message here as I did not find a bugtracker on the website.
>>
>> If this is the wrong place, I would kindly apologize and ask you to redirect me to the proper place,
>>
>> Thank you.
>>
>> Description of the issue:
>>
>> I am using pktgen-dpdk to replay a pcap file containing exactly 1 packet.
>>
>> The packet in question is generated using this Scapy command:
>>
>> pkt=(Ether(src="ec:0d:9a:37:d1:ab",dst="7c:fe:90:31:0d:52")/Dot1Q(vlan=2)/IP(dst="192.168.0.254")/UDP(sport=1020,dport=1021)/Raw(RandBin(size=8500)))
>>
>> The pcap is then replayed in pktgen-dpdk:
>>
>> ./app/app/x86_64-native-linuxapp-gcc/pktgen -l 0-7 -- -m [1-7].0 -s 0:pcap/8500Bpp.pcap
>>
>> When I run this on a machine with Mellanox ConnectX-4 NIC (MCX4), the switch towards which I generate traffic gets a strange behaviour
>>
>> #sh int et29/1 | i rate
>>    5 seconds input rate 39.4 Gbps (98.4% with framing overhead), 0 packets/sec
>>
>> A capture of this traffic (I used a monitor session to redirect all to a different port, connected to a machine on which I ran tcpdump) gives me this:
>>
>> 19:04:50.210792 00:00:00:00:00:00 (oui Ethernet) > 00:00:00:00:00:00 (oui Ethernet) Null Unnumbered, ef, Flags [Poll], length 1500
>> 19:04:50.210795 00:00:00:00:00:00 (oui Ethernet) > 00:00:00:00:00:00 (oui Ethernet) Null Unnumbered, ef, Flags [Poll], length 1500
>> 19:04:50.210796 00:00:00:00:00:00 (oui Ethernet) > 00:00:00:00:00:00 (oui Ethernet) Null Unnumbered, ef, Flags [Poll], length 1500
>> 19:04:50.210797 00:00:00:00:00:00 (oui Ethernet) > 00:00:00:00:00:00 (oui Ethernet) Null Unnumbered, ef, Flags [Poll], length 1500
>> 19:04:50.210799 00:00:00:00:00:00 (oui Ethernet) > 00:00:00:00:00:00 (oui Ethernet) Null Unnumbered, ef, Flags [Poll], length 1500
>>
>> The issue cannot be reproduced if any of the following conditions is met:
>>
>> - Set the size in the Raw(RandBin()) to a value lower than 1500
>>
>> - Send the packet from a Mellanox ConnectX-3 (MCX3) NIC (both machines are indentical in terms of software).
>>
>> Is this a known problem ?
>>
>> I remain available for any question you may have.
>>
>> Regards,
>>
>> -- 
>> Damien Clabaut
>> R&D vRouter
>> ovh.qc.ca
>>

-- 
Damien Clabaut
R&D vRouter
ovh.qc.ca