use trex test vpp performance, memif can't connnect - cisco

Question

The goal is to connect TREX packet generator with VPP memif interface on the same Host. The memif Interface fails to get connected with the following logs
Failed with info:
Apr 28 15:12:24 xx[370159]: memif_connect_client(): Failed to connect socket: /run/vpp/memif.sock.
Apr 28 15:12:25 xx[370159]: EAL: Error - exiting with code: 1#012 Cause:
Apr 28 15:12:25 xx[370159]: rte_eth_dev_start: err=-1, port=0
vpp version: 19.08.3
trex version: v2.89
vpp# show memif
sockets
id listener filename
0 yes (2) /run/vpp/memif.sock
interface memif0/0
socket-id 0 id 0 mode ethernet
flags admin-up
listener-fd 49 conn-fd 0
num-s2m-rings 0 num-m2s-rings 0 buffer-size 0 num-regions 0
interface memif0/1
socket-id 0 id 1 mode ethernet
flags admin-up
listener-fd 49 conn-fd 0
num-s2m-rings 0 num-m2s-rings 0 buffer-size 0 num-regions 0
# cat /etc/trex_cfg.yaml**
- version: 2
interfaces: ["--vdev=net_memif0,role=slave,id=0,socket=/run/vpp/memif.sock",
"--vdev=net_memif1,role=slave,id=1,socket=/run/vpp/memif.sock"]
port_info:
- ip: 172.21.0.253
default_gw: 172.21.0.254
- ip: 192.168.1.254
default_gw: 192.168.1.253
platform:
master_thread_id: 16
latency_thread_id: 17
dual_if:
- socket: 0
threads: [18,19]

Answer 1

DPDK memif PMD has two modes of operation
Client mode
Server mode
The sequence of start also affects how memif communicate and connects to listener (server).
So if we need to make VPP as server and TREX as client use (always start VPP first and create memif interface)
create interface memif id 0 master
set interface state memif0/0 up
set interface ip address memif0/0 12.12.5.1/24
and
--vdev=net_memif0,role=client,id=0,socket=/run/vpp/memif.sock
if we need to make TREX server and VPP client use (always start TREX first)
--vdev=net_memif0,role=server,id=0,socket=/run/vpp/memif.sock
and
create interface memif id 0 slave
set interface state memif0/0 up
set interface ip address memif0/0 12.12.5.2/24
note:
if more than 1 interface is required, ensure VPP creates memif interface 0 and 1 on separate sockets.
tested the same with dpdk-pktgen and vpp.

Answer 2

Since the Trex 2.92 has been upgraded to use DPDK version 21.02
In interface in /etc/trex_cfg.yaml, instead of:
interfaces: ["--vdev=net_memif0,role=slave,id=0,socket=/run/vpp/memif.sock",
it should be
interfaces: ["--vdev=net_memif0,role=slave,id=0,socket-abstract=no,socket=/run/vpp/memif.sock",
as by default it assumes the socket path as raw socket path.