Connect Cisco IXM with UDP Packet Forwarder

This section contains instructions for connecting to The Things Stack using Semtech UDP Packet Forwarder.

To connect the gateway via UDP packet forwarder, first follow these instructions to obtain global_conf.json file, then follow instructions below.

Packet Forwarder Configuration

To run the packet forwarder, we’ll make use of the container that is running on the gateway at all times.

Gateway# request shell container-console

You will be requested to enter the System Password. By default this is admin.

Create the directory to store the Packet Forwarder configuration:

bash-3.2# mkdir /etc/pktfwd

Copy the packet forwarder to /etc/pktfwd:

bash-3.2# cp /tools/pkt_forwarder /etc/pktfwd/pkt_forwarder

Retrieve configuration from the Gateway Configuration Server

The Gateway Configuration Server can be used to retrieve a proper global_conf.json configuration file for your gateway. Follow instructions here.

Copy the downloaded global_conf.json configuration template as config.json to /etc/pktfwd:

bash-3.2# cp config.json /etc/pktfwd/config.json

You can now test the packet forwarder by executing:

bash-3.2# /etc/pktfwd/pkt_forwarder -c /etc/pktfwd/config.json -g/dev/ttyS1

Your gateway will connect to The Things Stack after a couple of minutes.

Now that we know the packet forwarder is running, let’s make it run automatically. Use this command:

bash-3.2# vi /etc/init.d/S60pkt_forwarder

Press the i key on your keyboard to start insert mode. Once finished editing, press ESC and enter :wq to write the file and quit.

Then copy paste the code below. Replace things.example.com with the name of your network after nslookup.

SCRIPT_DIR=/etc/pktfwd
SCRIPT=$SCRIPT_DIR/pkt_forwarder
CONFIG=$SCRIPT_DIR/config.json

PIDFILE=/var/run/pkt_forwarder.pid
LOGFILE=/var/log/pkt_forwarder.log

export NETWORKIP=$(nslookup things.example.com | grep -E -o "([0-9]{1,3}[\.]){3}[0-9]{1,3}" | tail -1)
sed -i 's/[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}/'$NETWORKIP'/g' "$CONFIG"

start() {
  echo "Starting pkt_forwarder"
  cd $SCRIPT_DIR
  start-stop-daemon \
        --start \
        --make-pidfile \
        --pidfile "$PIFDILE" \
        --background \
        --startas /bin/bash -- -c "exec $SCRIPT -- -c $CONFIG -g /dev/ttyS1 >> $LOGFILE 2>&1"
  echo $?
}

stop() {
  echo "Stopping pkt_forwarder"
  start-stop-daemon \
        --stop \
        --oknodo \
        --quiet \
        --pidfile "$PIDFILE"
}

restart() {
  stop
  sleep 1
  start
}

case "$1" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart|reload)
    restart
    ;;
  *)
    echo "Usage: $0 {start|stop|restart}"
    exit 1
esac

exit $?

Then make the init script executable:

bash-3.2# chmod +x /etc/init.d/S60pkt_forwarder

To enable it immediately, execute:

bash-3.2# /etc/init.d/S60pkt_forwarder start

You can now reboot the gateway, it can take up to 4 minutes.

If the gateway does not connect to the The Things Stack after a few minutes, you can check the log file to see if the packet forwarder started properly.

bash-3.2# tail -100 var/log/pkt_forwarder.log

GPS warnings may appear, which means the packet forwarder started.

If the radio failed to start, disconnect and reconnect the power supply to power-cycle the gateway.