[dpdk-users] DPDK on MLX4: Packets exchange problem

[dpdk-users] DPDK on MLX4: Packets exchange problem

[Harold Demure]

Hello,
  I am trying to write a simple UDP-based client server application
starting from the load-balancer example shipped with the dpdk libs.
I have setup the server basically copying the code of the example, and both
I/O and application threads seem to be up and running.

As a first step, I wrote the client side using standard socket programming.
I manage to send a packet (I see it using tpcdump), but the dpdk i/o thread
seems to be unaware of it.

Note that client and server are on the same machine, even though the client
sends the packet from another interface. Also, I use a mlx4 driver, so I
did not explicitly bind the NIC to dpdk using the proper script: as a
result, while running my server, I can ping the server. Still, tcpdump does
not acknowledge the reception of the message I send.

My environment is the following

DPDK: v  2.2

MLNX_OFED_LINUX-3.1-1.0.3-ubuntu14.04-x86_64

My NIC : 05:00.0 Ethernet controller: Mellanox Technologies MT27520 Family
[ConnectX-3 Pro]

My machine runs a 3.19.0-47-generic on Ubuntu 14.04.

CPU is Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz  2x8 cores


My questions are the following

1) Do you have any idea of what I can be doing wrong? Most likely it is a
rookie mistake. I am even starting to suspect that a DPDK server needs a
DPDK client, but this puzzles me.

2) Eventually, I am going to write a dpdk client as well. Is there any good
tutorial-like example I can refer to to see how to properly build
 eth->ipv4->udp packets to be exchanged between my client and server?


Thank you for your kind help.

Kind regards,

  Harold