Both ROS and ROS 2 allows you to run nodes on different physical machines as long as they are in the same LAN network. Therefore to run ROS on robotic system distributed among multiple networks VPN is needed.
Husarnet is a peer-to-peer, low-latency and lightweight VPN dedicated for robotics applications. In this short guide we will show you how to configure ROS 2 to make it work with Husarnet VPN client.
Basically "configure ROS 2" means "configure DDS" that is an abstraction layer ROS 2 is based on. To use Husarnet with DDS some preconfiguration is needed. The specific configuration depends on which DDS implementation is used, but generally peers from Husarnet should be added to an XML configuration file.
In the next sections we will present how to configure two most popular DDS implementations on system running ROS 2: Eclipse Cyclone DDS and eProsima Fast DDS. They both just work with Husarnet so the choice is yours.
Let's start with creating a VPN network for your devices...
Execute this command on each physical device you need to connect.
Remember to run:
after installation process is finished.
Add your physical devices to the same Husarnet network, by executing following commands on each of them:
More information at: Getting Started Guide for Linux
Default DDS implementation used in ROS 2 Dashing is RMW FastRTPS. We will replace that by Eclipse Cyclone DDS. There are two options: install from sources or from apt package.
When using ROS 2 Foxy and later you can skip this step and install as a binary package
In ROS 2 later than Dashing you can install as apt package
Create communication settings file under this path
To make communication work you have to set some params as follows:
You can provide Peer as IPv6 address or hostname from Husarnet.
IMPORTANT: Provide all peers <hostnames/IPv6 address>, (chose one) in every machine remember to use  .
<AllowMulticast>false</AllowMulticast>. At the time of writing this file multicast is not supported by Husarnet so it's necessary to disable this. Multicast feature will be added soon.
<Transport>udp6</Transport>. It's necessary to use IPv6 but Cyclone doesn't allow to mix IPv4 with IPv6 so every node must communicate over IPv6.
<Peers><Peer address="[IPV6-address]"/></Peers>. Here appropriate IP addresses should be filled, you can take this address form Husarnet WebUI. Safe method is to provide address of local IPv6 and remote machines.
If you need information about params check cyclonedds-manual
Add changes to .bashrc file to use that configuration every time you boot your system. Open a new terminal and execute:
Run demo publisher and subscriber:
At the first physical machine execute in the terminal:
And this command at the second:
Create a Fast DDS configuration file in your ROS 2 workspace:
To make the communication work, you have to set some parameters as shown in the following template.
IMPORTANT: Provide all peers under
Set this file as default profile in your
.bashrc file, so as to use this configuration every time you boot your system. Open a new terminal and execute:
Now you will be able to use your default ROS 2 tools with Husarnet:
As you can see using Husarnet with ROS 2 and Cyclone DDS or Fast DDS is very easy.