Prerequisites
-------------
1. Compile symmetric_mp example application::
meson configure -Dexamples=multi_process/symmetric_mp x86_64-native-linuxapp-gcc
ninja -C x86_64-native-linuxapp-gcc

Steps
-----
1. Launch vhost testpmd as primary process::

./x86_64-native-linuxapp-gcc/examples/dpdk-symmetric_mp -l 1 -n 4 \
--vdev 'net_vhost,iface=vhost-net,queues=2,client=1' \
--vdev 'net_vhost1,iface=vhost-net1,queues=2,client=1' \
--proc-type=auto -- -p 3 --num-procs=2 --proc-id=0

2. Launch vhost testpmd as secondary process::  

./x86_64-native-linuxapp-gcc/examples/dpdk-symmetric_mp -l 2 -n 4 \
--vdev 'net_vhost,iface=vhost-net,queues=2,client=1' \
--vdev 'net_vhost1,iface=vhost-net1,queues=2,client=1' \
--proc-type=auto -- -p 3 --num-procs=2 --proc-id=1

3. Launch virtio-user::
./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -n 4 -l 7-8 --no-pci --file-prefix=virtio1 \
--vdev=net_virtio_user1,mac=00:01:02:03:04:05,path=./vhost-net,queues=2,server=1,mrg_rxbuf=0,in_order=0 \
-- -i --nb-cores=1 --rxq=2 --txq=2 --txd=1024 --rxd=1024

when launch virtio-user:
VHOST_CONFIG: (0) device not found.