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

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
connect raspi to lan and power, no keyboard / mouse / monitor is required
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]
```

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)
....

(optional) add public key as authorized ssh key

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

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

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:~$

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

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.