Now, put "InfluxDB + Telegraf + Chronograf" in CentOS8 and try to control the temperature of multiple Raspberry pi4.

I want to control the temperature of Raspberry Pi 4B

There are multiple Pi4s with explosive heat, and I was worried about the CPU temperature during the hot summer, so I had no choice but to hit vcgencmd measure_temp in 2020. I was told that it's easier to use "Chronograf", but the procedure is messy, isn't it? I left it ww.

"InfluxDB + Telegraf + Chronograf" Is it delicious now?

InfluxDB is an open source time series database developed by InfluxData. Telegraf + Chronograf is also developed by this company, so it's relatively easy to build.

By the way, Telegraf is a metrics collector dedicated to InfluxDB. Chronograf is a visualization dashboard framework dedicated to InfluxDB.

Maybe, but easier than doing it with (NET-SNMP + MRTG). This is recommended.

Constitution

Let's make it like this. CentOS8 : InfluxDB , Chronograf Pi4B : Telegraf InfluxDB : influxdb-1.8.3.x86_64.rpm Chronograf : chronograf-1.8.5.x86_64.rpm Telegraf : telegraf-1.15.3-1.x86_64.rpm / telegraf-1.15.3

It looks like the figure below

Install InfluxDB, Chronograf on CentOS

InfluxDB may be powerless with Pi? Since I read the article, InfluxDB, Chronograf will try to insuko on the side with a little power.

InfluxDB installation

You can download rpm and install it, but the yum command is easier, so create the following file.

/etc/yum.repos.d/influxdb.repo

[influxdb]
name = InfluxDB Repository
baseurl = https://repos.influxdata.com/rhel/8/x86_64/stable/
enabled = 1
gpgcheck = 1
gpgkey = https://repos.influxdata.com/influxdb.key

Install with yum. only this.

$ sudo dnf makecache
$ sudo yum install influxdb
$ systemctl enable --now influxdb.service

You will be able to create a database using the influx command. InfluxDB also requires a firewall configuration to use the 8086 port.

What is the time series database InfluxDB?

Install Chronograf

I'll put this from the rpm package. Chronograf requires a firewall configuration to use port 8888.

$ wget https://repos.influxdata.com/rhel/8/x86_64/stable/chronograf-1.8.5.x86_64.rpm
$ sudo yum localinstall chronograf-1.8.5.x86_64.rpm
$ sudo systemctl enable --now chronograf
$ sudo systemctl status chronograf

Install it for the time being and set it later.

Install Telegraf on CentOS / Pi4

Install the Telegraf agent on the OS you want to monitor. Note that the command to inscore is slightly different from CentOS / Pi4.

Install Telegraf on CentOS

Modify the configuration file

$ wget https://repos.influxdata.com/rhel/8/x86_64/stable/telegraf-1.15.3-1.x86_64.rpm
$ sudo yum localinstall telegraf-1.15.3-1.x86_64.rpm
$ sudo systemctl enable --now telegraf
$ sudo systemctl status telegraf

Install Telegraf on Pi4

$ sudo curl https://repos.influxdata.com/influxdb.key | apt-key add -
$ sudo vi /etc/apt/sources.list.d/influxdb.list

deb https://repos.influxdata.com/debian buster stable

$ sudo apt update
$ sudo apt install telegraf
$ sudo systemctl enable --now telegraf
$ systemctl status telegraf.service

Modify telegraf.conf

Make the minimum settings for telegraf.conf. I don't think it's difficult.

/etc/telegraf/telegraf.conf

[agent]
  urls = ["http://192.xxx.yyy.zzz:8086"]  #InfluxDB instrumented IP
  database = "telegraf"
  retention_policy = ""
  write_consistency = "any"
  timeout = "5s"

after that. Reboot (if troublesome).

Try starting Chronograf

Try starting Chronograf. Access port 8888. I have a feeling of refusal because it doesn't support Japanese, but let's do our best here.

[First Chronograf that is easy to understand](https://www.ultra-noob.com/blog/2020-04-02-%E3%82%84%E3%81%9F%E3%82%89%E5 % 88% 86% E3% 81% 8B% E3% 82% 8A% E3% 82% 84% E3% 81% 99% E3% 81% 84% E5% 88% 9D% E3% 82% 81% E3% 81 % A6% E3% 81% AEchronograf /)

If the Telegraf agent is running, you should see something like this:

Raspberry pi4 temperature control

Since the Raspberry pi has a temperature sensor, let's create a command to register the CPU temperature in InfluxDB via the Telegraf agent. I thought that the threshold was high, but it was relatively easy, so it should be applicable in various ways.

・ [[Raspberry Pi + InfluxDB + Telegraf] How to record the CPU temperature of Raspberry Pi](https://www.ultra-noob.com/blog/2020-08-29-%E3%80%90Raspberry%20Pi% 20_% 20InfluxDB% 20_% 20 Telegraf% E3% 80% 91% E3% 83% A9% E3% 82% BA% E3% 83% 91% E3% 82% A4% E3% 81% AECPU% E6% B8% A9% E5% BA% A6% E3% 82% 92% E8% A8% 98% E9% 8C% B2% E3% 81% 99% E3% 82% 8B% E6% 96% B9% E6% B3% 95 /) ・ How to measure a Raspberry Pi's temperature and CPU frequency with Telegraf

It's a tankopi, but this kind of thing needs to be experienced. / usr / local / bin / rpi-temp Create a file.

#!/bin/bash

awk '{print $1/1000}' /sys/class/thermal/thermal_zone0/temp

Next, switch to execution mode. I'll hit it. The value comes out. I need this.

$ cd /usr/local/bin
$ sudo chmod 755 rpi-temp
$ ./rpi-temp
44.79

If you can confirm this state, put the following near the end of /etc/telegraf/telegraf.conf.

/etc/telegraf/telegraf.conf

[[inputs.exec]]
  commands = ["/usr/local/bin/rpi-temp"]
  name_override = "rpi_temp"
  data_format = "value"
  data_type = "float"

After that, restart the Telegraf agent. You don't have to restart pi4.

$ systemctl restart telegraf.service

Check if the temperature sensor information of pi4 is available on Chronograf.

Wow, super easy than setting MRTG.

Summary for the time being

・ How To Install InfluxDB on CentOS 8 / RHEL 8 ・ Obtain a subr resource with Telegraf and store it in InfluxDB ・ [Comparison] Grafana vs. Chronograf --Compare visualization tools- ・ Build a monitoring environment with TICK stack (Telegraf + InfluxDB + Chronograf + Kapacitor) ・ [Preparation for Iot home environment] Setting of database InfluxDB to save sensed data with Raspberry Pi ・ Spring boot metrics monitoring using TICK stack