Networking with multiple Zephyr instances

Prerequisites
Basic Setup

This page describes how to set up a virtual network between multiple Zephyr instances. The Zephyr instances could be running inside QEMU or could be native_posix board processes. The Linux host can be used to route network traffic between these systems.

Prerequisites 

On the Linux Host, fetch the Zephyr net-tools project, which is located in a separate Git repository:

git clone https://github.com/zephyrproject-rtos/net-tools

Basic Setup 

For the steps below, you will need five terminal windows:

Terminal #1 and #2 are terminal windows with net-tools being the current directory (cd net-tools)
Terminal #3, where you setup bridging in Linux host
Terminal #4 and #5 are your usual Zephyr development terminal, with the Zephyr environment initialized.

As there are multiple ways to setup the Zephyr network, the example below uses qemu_x86 board with e1000 Ethernet controller and native_posix board to simplify the setup instructions. You can use other QEMU boards and drivers if needed, see Networking with QEMU Ethernet for details. You can also use two or more native_posix board Zephyr instances and connect them together.

Step 1 - Create configuration files 

Before starting QEMU with network connectivity, a network interfaces for each Zephyr instance should be created in the host system. The default setup for creating network interface cannot be used here as that is for connecting one Zephyr instance to Linux host.

For Zephyr instance #1, create file called zephyr1.conf to net-tools project, or to some other suitable directory.

# Configuration file for setting IP addresses for a network interface.
INTERFACE="$1"
HWADDR="00:00:5e:00:53:11"
IPV6_ADDR_1="2001:db8:100::2"
IPV6_ROUTE_1="2001:db8:100::/64"
IPV4_ADDR_1="198.51.100.2/24"
IPV4_ROUTE_1="198.51.100.0/24"
ip link set dev $INTERFACE up
ip link set dev $INTERFACE address $HWADDR
ip -6 address add $IPV6_ADDR_1 dev $INTERFACE nodad
ip -6 route add $IPV6_ROUTE_1 dev $INTERFACE
ip address add $IPV4_ADDR_1 dev $INTERFACE
ip route add $IPV4_ROUTE_1 dev $INTERFACE > /dev/null 2>&1

For Zephyr instance #2, create file called zephyr2.conf to net-tools project, or to some other suitable directory.

# Configuration file for setting IP addresses for a network interface.
INTERFACE="$1"
HWADDR="00:00:5e:00:53:22"
IPV6_ADDR_1="2001:db8:200::2"
IPV6_ROUTE_1="2001:db8:200::/64"
IPV4_ADDR_1="203.0.113.2/24"
IPV4_ROUTE_1="203.0.113.0/24"
ip link set dev $INTERFACE up
ip link set dev $INTERFACE address $HWADDR
ip -6 address add $IPV6_ADDR_1 dev $INTERFACE nodad
ip -6 route add $IPV6_ROUTE_1 dev $INTERFACE
ip address add $IPV4_ADDR_1 dev $INTERFACE
ip route add $IPV4_ROUTE_1 dev $INTERFACE > /dev/null 2>&1

Step 2 - Create Ethernet interfaces 

The following net-setup.sh commands should be typed in net-tools directory (cd net-tools).

In terminal #1, type:

./net-setup.sh -c zephyr1.conf -i zeth.1

In terminal #2, type:

./net-setup.sh -c zephyr2.conf -i zeth.2

Step 3 - Setup network bridging 

In terminal #3, type:

sudo brctl addbr zeth-br
sudo brctl addif zeth-br zeth.1
sudo brctl addif zeth-br zeth.2
sudo ifconfig zeth-br up

Step 4 - Start Zephyr instances 

In this example we start Socket Echo Server and Socket Echo Client applications. You can use other applications too as needed.

In terminal #4, if you are using QEMU, type this:

west build -d build/server -b qemu_x86 -t run \
   samples/net/sockets/echo_server -- \
   -DOVERLAY_CONFIG=overlay-e1000.conf \
   -DCONFIG_NET_CONFIG_MY_IPV4_ADDR=\"198.51.100.1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV4_ADDR=\"203.0.113.1\" \
   -DCONFIG_NET_CONFIG_MY_IPV6_ADDR=\"2001:db8:100::1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV6_ADDR=\"2001:db8:200::1\" \
   -DCONFIG_NET_CONFIG_MY_IPV4_GW=\"203.0.113.1\" \
   -DCONFIG_ETH_QEMU_IFACE_NAME=\"zeth.1\" \
   -DCONFIG_ETH_QEMU_EXTRA_ARGS=\"mac=00:00:5e:00:53:01\"

or if you want to use native_posix board, type this:

west build -d build/server -b native_posix -t run \
   samples/net/sockets/echo_server -- \
   -DCONFIG_NET_CONFIG_MY_IPV4_ADDR=\"198.51.100.1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV4_ADDR=\"203.0.113.1\" \
   -DCONFIG_NET_CONFIG_MY_IPV6_ADDR=\"2001:db8:100::1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV6_ADDR=\"2001:db8:200::1\" \
   -DCONFIG_NET_CONFIG_MY_IPV4_GW=\"203.0.113.1\" \
   -DCONFIG_ETH_NATIVE_POSIX_DRV_NAME=\"zeth.1\" \
   -DCONFIG_ETH_NATIVE_POSIX_MAC_ADDR=\"00:00:5e:00:53:01\" \
   -DCONFIG_ETH_NATIVE_POSIX_RANDOM_MAC=n

In terminal #5, if you are using QEMU, type this:

west build -d build/client -b qemu_x86 -t run \
   samples/net/sockets/echo_client -- \
   -DOVERLAY_CONFIG=overlay-e1000.conf \
   -DCONFIG_NET_CONFIG_MY_IPV4_ADDR=\"203.0.113.1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV4_ADDR=\"198.51.100.1\" \
   -DCONFIG_NET_CONFIG_MY_IPV6_ADDR=\"2001:db8:200::1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV6_ADDR=\"2001:db8:100::1\" \
   -DCONFIG_NET_CONFIG_MY_IPV4_GW=\"198.51.100.1\" \
   -DCONFIG_ETH_QEMU_IFACE_NAME=\"zeth.2\" \
   -DCONFIG_ETH_QEMU_EXTRA_ARGS=\"mac=00:00:5e:00:53:02\"

or if you want to use native_posix board, type this:

west build -d build/client -b native_posix -t run \
   samples/net/sockets/echo_client -- \
   -DCONFIG_NET_CONFIG_MY_IPV4_ADDR=\"203.0.113.1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV4_ADDR=\"198.51.100.1\" \
   -DCONFIG_NET_CONFIG_MY_IPV6_ADDR=\"2001:db8:200::1\" \
   -DCONFIG_NET_CONFIG_PEER_IPV6_ADDR=\"2001:db8:100::1\" \
   -DCONFIG_NET_CONFIG_MY_IPV4_GW=\"198.51.100.1\" \
   -DCONFIG_ETH_NATIVE_POSIX_DRV_NAME=\"zeth.2\" \
   -DCONFIG_ETH_NATIVE_POSIX_MAC_ADDR=\"00:00:5e:00:53:02\" \
   -DCONFIG_ETH_NATIVE_POSIX_RANDOM_MAC=n

Also if you have firewall enabled in your host, you need to allow traffic between zeth.1, zeth.2 and zeth-br interfaces.

Networking with multiple Zephyr instances

Prerequisites

Basic Setup

Step 1 - Create configuration files

Step 2 - Create Ethernet interfaces

Step 3 - Setup network bridging

Step 4 - Start Zephyr instances