Gruppo Meteo/HowTo/LorawanGateway

LoRaWAN Gateway on rapberry, IMST iC880A Concentrator 868MHz, Centos 7

Main characteristics

• User lorawan packet forwarder ( TTN legacy mode )
• Remote access using ssh tunneling
• Hardware reset for IMST concentrator
• Autorestart services and network connections
• Use system users for services (none run as root or privileged users)
• All software (not configuration) is packaged and use standard public repo (not signed)
• Use firewalld

Assemble the gateway

Parts:

• Raspberry 3
• iC880A - LoRaWAN® Concentrator 868MHz https://wireless-solutions.de/products/long-range-radio/ic880a.html
• IP65 Box
• LM2596 DC-DC 3-35V adjustable step-down power Supply module http://hobbycomponents.com/power/215-lm2596-dc-dc-3-35v-adjustable-step-down-power-supply-module
• 2200uF capacitor
• internet key with SIM card
• power supply 12V 2A

Assemble the gateway as described at: https://github.com/ttn-zh/ic880a-gateway/wiki

Regulate the DC-DC power Supply to output 5.0V Connect the capacitor to the output of DC-DC power Supply Connect power supply to DC-DC input Connect DC-DC output to raspberry

Operative system

Follow https://wiki.centos.org/SpecialInterestGroup/AltArch/Arm32/RaspberryPi3

enable epel:

cat > /etc/yum.repos.d/epel.repo << EOF
[epel]
name=Epel rebuild for armhfp
baseurl=https://armv7.dev.centos.org/repodir/epel-pass-1/
enabled=1
gpgcheck=0

EOF

enable ttn:

cd /etc/yum.repos.d
wget http://rmap.cc/repo/ttn/rmapcentos.repo

change root password!

Install packages

TOBEDONE

chkconfig ttn-gateway on chkconfig ttn-imstreset-setgpio on

Autossh

• attivare autossh, ossia un tunneling ssh su macchina pubblica per

permettere l'accesso remoto di amministrazione; infatti la connesione tramite wifi o ethernet o GSM non espongono un ip pubblico (almeno senza fare un reindirizzamento di porta):

yum install autossh da root:

ssh-keygen
ssh-copy-id 

/usr/lib/systemd/system/autossh.service

[Unit]
Description=Autossh tunneling
After=network.target

[Service]
#User=ttn
#Group=ttn
WorkingDirectory=/root
#ExecStart=/usr/bin/autossh -M 5023  -N -R 5022:localhost:22 pat1@ttn.rmap.it
ExecStart=/usr/bin/autossh -M 0 -o "ServerAliveInterval 60" -o "ServerAliveCountMax 3" -N -R 5022:localhost:22 <user>@<remotehost>
SyslogIdentifier=autossh
Restart=always
RestartSec=30

[Install]
WantedBy=multi-user.target

systemctl daemon-reload
service autossh start
chkconfig autossh on

ora dalla macchina remota si può fare:

ssh root@localhost -p5022

Monit

GSM

/etc/monit.d/gsm-connection (change usb_modeswitch command and serial port to adapt to your gsm modem):

CHECK PROGRAM check_gsm PATH /usr/local/bin/check_gsm TIMEOUT 30 SECONDS
   if status != 0 then start

   start program = "/sbin/usb_modeswitch -v 12d1 -p 14fe -c /usr/share/usb_modeswitch/12d1:14fe ; sleep 10; /usr/bin/nmcli device connect ttyUSB2"
   stop program  = "/usr/bin/nmcli device disconnect ttyUSB2"

/usr/local/bin/check_gsm

#!/bin/bash
set -e

# "Check Mobile Broadband Connection." 

# testing...to see if gsm is on the list of active devices

       LC_ALL=C nmcli -t -f TYPE,STATE dev | grep -q "^gsm:connected$"

Packet forwarder

/usr/local/bin/check_gateway (change your gateway id and coordinate):

#!/usr/bin/python

import urllib2
import json
import dateutil.parser
import datetime
import sys

GATEWAYID="eui-0ceee6fffe9da82e"
LAT="44.48842723017417"
LON="11.26079806901295"

body=urllib2.urlopen("https://www.thethingsnetwork.org/gateway-data/location?latitude="+LAT+"&longitude="+LON+"&distance=15000").read()
gatewaydata=json.loads(body)
print gatewaydata[GATEWAYID]["last_seen"]

lastseen = dateutil.parser.parse(gatewaydata[GATEWAYID]["last_seen"]).replace(tzinfo=None)
now=datetime.datetime.utcnow()
print lastseen
print now

elapsed=now-lastseen
print "elapsed: ", elapsed
if ( elapsed > datetime.timedelta(seconds=300)):
   sys.exit(1)

sys.exit(0)

/etc/monit.d/gateway-connection

CHECK PROGRAM gateway-connection PATH /usr/local/bin/check_gateway TIMEOUT 30 SECONDS
   if status != 0 then restart

   start program = "/usr/sbin/service ttn-gateway start"
   stop program  = "/usr/sbin/service ttn-gateway stop"

   every 5 cycles

Activate monit

chkconfig monit on
service monit start