2. Live Migration of VM with Virtio on host running vhost_user

2.1. Overview

Live Migration of a VM with DPDK Virtio PMD on a host which is running the Vhost sample application (vhost-switch) and using the DPDK PMD (ixgbe or i40e).

The Vhost sample application uses VMDQ so SRIOV must be disabled on the NIC’s.

The following sections show an example of how to do this migration.

2.2. Test Setup

To test the Live Migration two servers with identical operating systems installed are used. KVM and QEMU is also required on the servers.

QEMU 2.5 is required for Live Migration of a VM with vhost_user running on the hosts.

In this example, the servers have Niantic and or Fortville NIC’s installed. The NIC’s on both servers are connected to a switch which is also connected to the traffic generator.

The switch is configured to broadcast traffic on all the NIC ports.

The ip address of host_server_1 is 10.237.212.46

The ip address of host_server_2 is 10.237.212.131

../_images/lm_vhost_user.svg

2.3. Live Migration steps

The sample scripts mentioned in the steps below can be found in the Sample host scripts and Sample VM scripts sections.

2.3.1. On host_server_1: Terminal 1

Setup DPDK on host_server_1

cd /root/dpdk/host_scripts
./setup_dpdk_on_host.sh

2.3.2. On host_server_1: Terminal 2

Bind the Niantic or Fortville NIC to igb_uio on host_server_1.

For Fortville NIC.

cd /root/dpdk/usertools
./dpdk-devbind.py -b igb_uio 0000:02:00.0

For Niantic NIC.

cd /root/dpdk/usertools
./dpdk-devbind.py -b igb_uio 0000:09:00.0

2.3.3. On host_server_1: Terminal 3

For Fortville and Niantic NIC’s reset SRIOV and run the vhost_user sample application (vhost-switch) on host_server_1.

cd /root/dpdk/host_scripts
./reset_vf_on_212_46.sh
./run_vhost_switch_on_host.sh

2.3.4. On host_server_1: Terminal 1

Start the VM on host_server_1

./vm_virtio_vhost_user.sh

2.3.5. On host_server_1: Terminal 4

Connect to the QEMU monitor on host_server_1.

cd /root/dpdk/host_scripts
./connect_to_qemu_mon_on_host.sh
(qemu)

2.3.6. On host_server_1: Terminal 1

In VM on host_server_1:

Setup DPDK in the VM and run testpmd in the VM.

cd /root/dpdk/vm_scripts
./setup_dpdk_in_vm.sh
./run_testpmd_in_vm.sh

testpmd> show port info all
testpmd> set fwd mac retry
testpmd> start tx_first
testpmd> show port stats all

Virtio traffic is seen at P1 and P2.

2.3.7. On host_server_2: Terminal 1

Set up DPDK on the host_server_2.

cd /root/dpdk/host_scripts
./setup_dpdk_on_host.sh

2.3.8. On host_server_2: Terminal 2

Bind the Niantic or Fortville NIC to igb_uio on host_server_2.

For Fortville NIC.

cd /root/dpdk/usertools
./dpdk-devbind.py -b igb_uio 0000:03:00.0

For Niantic NIC.

cd /root/dpdk/usertools
./dpdk-devbind.py -b igb_uio 0000:06:00.0

2.3.9. On host_server_2: Terminal 3

For Fortville and Niantic NIC’s reset SRIOV, and run the vhost_user sample application on host_server_2.

cd /root/dpdk/host_scripts
./reset_vf_on_212_131.sh
./run_vhost_switch_on_host.sh

2.3.10. On host_server_2: Terminal 1

Start the VM on host_server_2.

./vm_virtio_vhost_user_migrate.sh

2.3.11. On host_server_2: Terminal 4

Connect to the QEMU monitor on host_server_2.

cd /root/dpdk/host_scripts
./connect_to_qemu_mon_on_host.sh
(qemu) info status
VM status: paused (inmigrate)
(qemu)

2.3.12. On host_server_1: Terminal 4

Check that switch is up before migrating the VM.

(qemu) migrate tcp:10.237.212.131:5555
(qemu) info status
VM status: paused (postmigrate)

(qemu) info migrate
capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off
Migration status: completed
total time: 11619 milliseconds
downtime: 5 milliseconds
setup: 7 milliseconds
transferred ram: 379699 kbytes
throughput: 267.82 mbps
remaining ram: 0 kbytes
total ram: 1590088 kbytes
duplicate: 303985 pages
skipped: 0 pages
normal: 94073 pages
normal bytes: 376292 kbytes
dirty sync count: 2
(qemu) quit

2.3.13. On host_server_2: Terminal 1

In VM on host_server_2:

Hit Enter key. This brings the user to the testpmd prompt.
testpmd>

2.3.14. On host_server_2: Terminal 4

In QEMU monitor on host_server_2

(qemu) info status
VM status: running

2.3.15. On host_server_2: Terminal 1

In VM on host_server_2:

testpmd> show port info all
testpmd> show port stats all

Virtio traffic is seen at P0 and P1.

2.4. Sample host scripts

2.4.1. reset_vf_on_212_46.sh

#!/bin/sh
# This script is run on the host 10.237.212.46 to reset SRIOV

# BDF for Fortville NIC is 0000:02:00.0
cat /sys/bus/pci/devices/0000\:02\:00.0/max_vfs
echo 0 > /sys/bus/pci/devices/0000\:02\:00.0/max_vfs
cat /sys/bus/pci/devices/0000\:02\:00.0/max_vfs

# BDF for Niantic NIC is 0000:09:00.0
cat /sys/bus/pci/devices/0000\:09\:00.0/max_vfs
echo 0 > /sys/bus/pci/devices/0000\:09\:00.0/max_vfs
cat /sys/bus/pci/devices/0000\:09\:00.0/max_vfs

2.4.2. vm_virtio_vhost_user.sh

#/bin/sh
# Script for use with vhost_user sample application
# The host system has 8 cpu's (0-7)

# Path to KVM tool
KVM_PATH="/usr/bin/qemu-system-x86_64"

# Guest Disk image
DISK_IMG="/home/user/disk_image/virt1_sml.disk"

# Number of guest cpus
VCPUS_NR="6"

# Memory
MEM=1024

VIRTIO_OPTIONS="csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off"

# Socket Path
SOCKET_PATH="/root/dpdk/host_scripts/usvhost"

taskset -c 2-7 $KVM_PATH \
 -enable-kvm \
 -m $MEM \
 -smp $VCPUS_NR \
 -object memory-backend-file,id=mem,size=1024M,mem-path=/mnt/huge,share=on \
 -numa node,memdev=mem,nodeid=0 \
 -cpu host \
 -name VM1 \
 -no-reboot \
 -net none \
 -vnc none \
 -nographic \
 -hda $DISK_IMG \
 -chardev socket,id=chr0,path=$SOCKET_PATH \
 -netdev type=vhost-user,id=net1,chardev=chr0,vhostforce \
 -device virtio-net-pci,netdev=net1,mac=CC:BB:BB:BB:BB:BB,$VIRTIO_OPTIONS \
 -chardev socket,id=chr1,path=$SOCKET_PATH \
 -netdev type=vhost-user,id=net2,chardev=chr1,vhostforce \
 -device virtio-net-pci,netdev=net2,mac=DD:BB:BB:BB:BB:BB,$VIRTIO_OPTIONS \
 -monitor telnet::3333,server,nowait

2.4.3. connect_to_qemu_mon_on_host.sh

#!/bin/sh
# This script is run on both hosts when the VM is up,
# to connect to the Qemu Monitor.

telnet 0 3333

2.4.4. reset_vf_on_212_131.sh

#!/bin/sh
# This script is run on the host 10.237.212.131 to reset SRIOV

# BDF for Niantic NIC is 0000:06:00.0
cat /sys/bus/pci/devices/0000\:06\:00.0/max_vfs
echo 0 > /sys/bus/pci/devices/0000\:06\:00.0/max_vfs
cat /sys/bus/pci/devices/0000\:06\:00.0/max_vfs

# BDF for Fortville NIC is 0000:03:00.0
cat /sys/bus/pci/devices/0000\:03\:00.0/max_vfs
echo 0 > /sys/bus/pci/devices/0000\:03\:00.0/max_vfs
cat /sys/bus/pci/devices/0000\:03\:00.0/max_vfs

2.4.5. vm_virtio_vhost_user_migrate.sh

#/bin/sh
# Script for use with vhost user sample application
# The host system has 8 cpu's (0-7)

# Path to KVM tool
KVM_PATH="/usr/bin/qemu-system-x86_64"

# Guest Disk image
DISK_IMG="/home/user/disk_image/virt1_sml.disk"

# Number of guest cpus
VCPUS_NR="6"

# Memory
MEM=1024

VIRTIO_OPTIONS="csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off"

# Socket Path
SOCKET_PATH="/root/dpdk/host_scripts/usvhost"

taskset -c 2-7 $KVM_PATH \
 -enable-kvm \
 -m $MEM \
 -smp $VCPUS_NR \
 -object memory-backend-file,id=mem,size=1024M,mem-path=/mnt/huge,share=on \
 -numa node,memdev=mem,nodeid=0 \
 -cpu host \
 -name VM1 \
 -no-reboot \
 -net none \
 -vnc none \
 -nographic \
 -hda $DISK_IMG \
 -chardev socket,id=chr0,path=$SOCKET_PATH \
 -netdev type=vhost-user,id=net1,chardev=chr0,vhostforce \
 -device virtio-net-pci,netdev=net1,mac=CC:BB:BB:BB:BB:BB,$VIRTIO_OPTIONS \
 -chardev socket,id=chr1,path=$SOCKET_PATH \
 -netdev type=vhost-user,id=net2,chardev=chr1,vhostforce \
 -device virtio-net-pci,netdev=net2,mac=DD:BB:BB:BB:BB:BB,$VIRTIO_OPTIONS \
 -incoming tcp:0:5555 \
 -monitor telnet::3333,server,nowait

2.5. Sample VM scripts

2.5.1. setup_dpdk_virtio_in_vm.sh

#!/bin/sh
# this script matches the vm_virtio_vhost_user script
# virtio port is 03
# virtio port is 04

cat  /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
cat  /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages

ifconfig -a
/root/dpdk/usertools/dpdk-devbind.py --status

rmmod virtio-pci

modprobe uio
insmod /root/dpdk/x86_64-default-linux-gcc/kmod/igb_uio.ko

/root/dpdk/usertools/dpdk-devbind.py -b igb_uio 0000:00:03.0
/root/dpdk/usertools/dpdk-devbind.py -b igb_uio 0000:00:04.0

/root/dpdk/usertools/dpdk-devbind.py --status

2.5.2. run_testpmd_in_vm.sh

#!/bin/sh
# Run testpmd for use with vhost_user sample app.
# test system has 8 cpus (0-7), use cpus 2-7 for VM

/root/dpdk/x86_64-default-linux-gcc/app/testpmd \
-l 0-5 -n 4 --socket-mem 350 -- --burst=64 --i