home-monitoring

Monitor and visualize energy and resource consumption using influx, telegraf and grafana on a raspberry pi.

Overview

The TIG-stack consisting of Telegraf, InfluxDB and Grafana provides the basis for this home monitoring solution. They are running together on a raspberry pi 4. Ubuntu is used as operating system.

Telegraf is used to gather the measurements from the following sources

• FritzBox via TR-094 / Universal PnP
• Kostal power inverter type Piko 3.6 (installed 2008)
• Kostal Plenticore 8.5 power inverter (installed 2020)

Manual Setup

The following values need adjustment when setting up another instance:

• raspi4ubuntu: hostname of the raspi ubuntu server
• telegrafpassword: the password for the telegraf user within the influx DB

ubuntu on raspi

1. Flash Ubuntu on a SD Card

   • Download Ubuntu Pi image
   • Current Version: ubuntu 20.04 LTS.
   • For the Raspberyy Pi 4 the 64 bit edition is recommended.
   • Follow the tutorial for flashing the image Hint: Writing to /dev/rdiskX instead of /dev/diskX will be 2-3 times faster.
   • Eject sd card and put it into the Raspberry

2. connect raspi to lan and power, no keyboard / mouse / monitor is required

3. use router / dhcp server / arp cache to determine IP address:

   My Raspberry Pi 4 uses the OUI DC-A6-32, so I can query the arp cache:

   $ arp -a | grep dc:a6:32
   ? (192.168.178.71) at dc:a6:32:50:9a:f9 on en0 ifscope [ethernet]

4. ssh into the remote raspi as user ubuntu with password ubuntu - changing the initial passworde is automatically requested right after login.

   $ ssh  ubuntu@192.168.178.71
   The authenticity of host '192.168.178.71 (192.168.178.71)' can't be established.
   ECDSA key fingerprint is ...
   Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
   ubuntu@192.168.178.71's password: ... 
   You are required to change your password immediately (administrator enforced)
   .... 

5. (optional) add public key as authorized ssh key

   # from within your workstation terminal
   ssh-copy-id -i ~/.ssh/id_rsa.pub ubuntu@raspi4ubuntu

6. basic system config

   # within ubuntu shell
   sudo apt-mark hold flash-kernel
   sudo apt-get update && sudo apt-get upgrade
   sudo dpkg-reconfigure tzdata
   sudo hostnamectl set-hostname raspi4ubuntu

Install TIG-Stack (Telegraf, InfluxDB, Grafana)

see also: complete tutorial

1. InfluxDB

   sudo curl -sL https://repos.influxdata.com/influxdb.key | sudo apt-key add -
   source /etc/lsb-release
   echo "deb https://repos.influxdata.com/${DISTRIB_ID,,} ${DISTRIB_CODENAME} stable" | sudo tee /etc/apt/sources.list.d/influxdb.list
   sudo apt update
   sudo apt install influxdb -y
   sudo systemctl start influxdb
   sudo systemctl enable influxdb
   # check that ports 8088 and 8086 are in LISTEN state
   netstat -plntu

   Create Database and User using the influx shell

   ubuntu@ubuntu:~$ influx
   Connected to http://localhost:8086 version 1.7.10
   InfluxDB shell version: 1.7.10
   > create database telegraf
   > create user telegraf with password 'telegrafpassword'
   > exit
   ubuntu@ubuntu:~$ 

2. Telegraf Agent

   sudo apt install telegraf -y
   sudo systemctl start telegraf
   sudo systemctl enable telegraf
   sudo systemctl status telegraf

   Create /etc/telegraf/telegraf.conf

   cd /etc/telegraf/
   sudo mv telegraf.conf telegraf.conf.default

   Provide new config (eg using sudo vi telegraf.conf):

   # Global Agent Configuration
   [agent]
     hostname = "raspi4ubuntu"
     flush_interval = "15s"
     interval = "15s"
   
   
   # Input Plugins
   [[inputs.cpu]]
       percpu = true
       totalcpu = true
       collect_cpu_time = false
       report_active = false
   [[inputs.disk]]
       ignore_fs = ["tmpfs", "devtmpfs", "devfs"]
   [[inputs.io]]
   [[inputs.mem]]
   [[inputs.net]]
   [[inputs.system]]
   [[inputs.swap]]
   [[inputs.netstat]]
   [[inputs.processes]]
   [[inputs.kernel]]
   
   # Output Plugin InfluxDB
   [[outputs.influxdb]]
     database = "telegraf"
     urls = [ "http://127.0.0.1:8086" ]
     username = "telegraf"
     password = "telegrafpassword"
   

   restart telegraf agent

   sudo systemctl restart telegraf

3. Grafana
   official install documentation recommends to use the enterprise edition

   sudo apt-get install -y apt-transport-https
   sudo apt-get install -y software-properties-common wget
   wget -q -O - https://packages.grafana.com/gpg.key | sudo apt-key add -
   sudo add-apt-repository "deb https://packages.grafana.com/enterprise/deb stable main"
   
   sudo apt-get install grafana-enterprise
   
   sudo systemctl start grafana-server
   sudo systemctl enable grafana-server
   netstat -plntu
   # check that grafana listens on port 3000

   Finish Grafana setup in the GUI:

   • open grafana in your browser (http at port 3000 served by raspi)
   • login to grafana using default credentials admin/admin
   • change default password
   • add InfluxDB datasource on http://localhost:8086/ using telegraf db and telegraf user credentials
   • import grafana dashboard e.g. system metrics "https://grafana.com/dashboards/5955"

TIG stack is now ready. But the only measurements are the system metrics of the raspi host system itself.

Gather metrics from Kostal Plenticore power inverter via modbus

Current power inverter from kostal have a modbus TCP interface. The modbus interface definition describes the available registers in chapter "3. MODBUS Register table".

The modbus interface has to be enabled within the inverter webgui and the port to be used may be changed there.

There is also a modbus input plugin available for telegraf.

The tricky part is to use the correct byte ordering and datatype, which is not specified in the kostal interface documentation. All registers with type Float in the register table need to be defined with data_type=FLOAT32-IEEE and byte_order="CDAB". I found this detail in netzkind's github project.

Furthermore, two consecutive register addresses need to be given.

Place file modbus-kostal.conf into /etc/telegraf/telegraf.d/. The controller = "tcp://192.168.178.65:1502" parameter needs to be adjusted to the inverter's actual ip adress and the configured modbus tcp port.