Border Router Install

Important Note : Before starting from this point, make sure you have followed all steps from Prerequisites and OpenThread Border Router setup on a Raspberry Pi 4 - RCP firmware

Build and Install the Open Thread Border Router core:

Browse back tou your development directory :

cd ~/border_router_dev

Then clone the OpenThread Border Router repository

git clone https://github.com/openthread/ot-br-posix

Browse into the cloned directory:

cd ot-br-posix

As of November 10th, this commit needs to be used to build an OpenThread RCP compliant with Matter

git checkout 72bb3d456

Run the bootstrap script to install build dependencies

sudo ./script/bootstrap

And finally launch the build procedure

sudo BACKBONE_ROUTER=1 INFRA_IF_NAME=eth0 ./script/setup
  

These two last steps can take a while

Update OTBR-Agent by replacing OTBR_AGENT_OPTS with below line

This will tell the otbr-agent that we are a Backbone Router on eth0 -B eth0, the tty interface we want to use /dev/ttyACM0 and the spinel baudrate uart-baudrate=460800 for the created wpan0 interface

sudo nano /etc/default/otbr-agent

OTBR_AGENT_OPTS="-I wpan0 -B eth0 spinel+hdlc+uart:///dev/ttyACM0?uart-baudrate=460800 trel://eth0"

Once the build and install procedure is over, simply reboot your Raspberry Pi:

sudo reboot now

Verify that the Border Router is up and running

Once the reboot is complete, and you have logged into the RPi again, check that otbr services are running fine:

sudo systemctl status | grep otbr

             ├─otbr-web.service
             │ └─448 /usr/sbin/otbr-web
             ├─otbr-agent.service
             │ └─441 /usr/sbin/otbr-agent -I wpan0 -B eth0 spinel+hdlc+uart:///dev/ttyACM0?uart-baudrate=460800 trel://eth0
  

As well as for the avahi service

sudo systemctl status | grep avahi

             ├─avahi-daemon.service
             │ ├─422 avahi-daemon: running [raspberrypi.local]
             │ └─426 avahi-daemon: chroot helper
  

At this point, the OpenThread Border Router should provide access to the ot-ctl tool from the shell

sudo ot-ctl state

disabled
Done
  

At this stage you can proceed creating your Thread Network on next page

Troubleshoot

If you precisely follow all of the previous sections (including git checkouts and prerequisites), you should have a perfectly running OpenThread Border Router

If somehow you still have issues, we identified a few scenarios where you might verifiy you did not miss any step :

sudo: unable to resolve host ubuntu: Name or service not known

This can happen when otbr installation messes up with /etc/hosts

To fix it, edit your file using sudo nano /etc/hosts so it looks as below :

127.0.0.1 localhost ubuntu

# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts
  

Note the added ubuntu at the end of first line

GCC seems to stall during build:

If you have an RPI 4 with less than 8GB RAM memory then you may need to setup swap memory before attempting to build any of the projects:

free -mh
sudo dd if=/dev/zero of=/home/swap bs=1024 count=640000
sudo mkswap /home/swap
sudo swapon /home/swap
  

Bootstrap fails because of permissions

Make sure you ran the script as sudo
Build fails because of permissions

Make sure you ran the script as sudo
ot-ctl connect session failed

It is usually due to an issue with otbr-agent unable to communicate with the RCP

cat syslog to identify the possible issue:
```
cat /var/log/syslog | grep otbr
```
If the issue is: RadioSpinelNoResponse
1. The obvious one, make sure you plugged the Thunderboard USB cable on the Raspberry Pi, and not on some other device
2. Make sure you edited the /etc/default/otbr-agent correctly
  
  As stated above, agent options should be :
```
OTBR_AGENT_OPTS="-I wpan0 -B eth0 spinel+hdlc+uart:///dev/ttyACM0?uart-baudrate=460800 trel://eth0"
```
3. Make sure that you did flash the correct binary : ot-rcp.s37
  
  It is a common mistake to flash ot-ftd, ot-mtd or ot-ncp variants
4. Make sure that you flashed a bootloader to your Thunderboard Sense 2
  
  See first section of this article. Without it the RCP firmware will not run, MCU ends in DefaultHanlder
5. Make sure that you have updated your Thunderboard Sense 2 Kit to a version > 1v3p0
  
  See the prerequisites section. This prevents the kit to disable flow control, hence blocking the UART communications
6. Finally if all of the above did not help make sure flow control is not forced enabled on your Thunderboard.
  
  To do so, you need to connect to the "ADMIN" console via Simplicity Studio
  
  A detailed Knowledge Base can be found here
Still not working ?

If none of the above worked, you can download a binary built during the writing of this guide here

DO NOT FORGET to flash a bootloader alongside it. Bootloader is provided here

If by using these 2 binaries you can get further, make sure that you ran through Building the RCP dongle firmware from github following all steps, especially git checkout to a known working version

If your Border Router Still does not run, make sure that you ran through Building the RCP dongle firmware from github following all steps, especially git checkout to a known working version

If not there at this stage you might request for help on building a border router on Silicon Labs Community

There is a dedicated Thread section in which you can ask community users for help