check_sht31

I. DESCRIPTION:

SHT31-D Sensor nagios plugin for Single Board Computers

Copyright (c) 2017 Frostbyte frostbytegr@gmail.com

Check environment temperature and humidity with SHT31-D via I2C

II. CREDITS:

• github.com/sfeakes - adafruit sht31 for raspberry pi code
• devel@nagios-plugins.org - plugin development guidelines

III. FEATURES:

• Output includes perfdata
• Threshold ranges (min/max) for both temperature and humidity
• Both warning and critical thresholds may be fully or partially omitted
  • Anything that has not been explicitly specified will be disabled
• Only allows for threshold ranges that are within the sensor's documented capabilities
  • Temperature: from -40 to 125 °C
  • Humidity: from 0 to 100 % RH
• Output validation against the sensor's CRC values and documented capabilities
  • If measured data are invalid, will retry every 1 second for a maximum of 3 times
• Execution of additional sensor commands
  • getEnvData, getSerial, getStatus, clearStatus, softReset, heaterEnable, heaterDisable

IV. SUPPORTED DEVICES:

• Raspberry Pi
• Raspberry Pi 2
• Raspberry Pi 3
• ASUS Tinker Board

V. GPIO HEADER PINOUT

NOTE: If using a Raspberry Pi, connect your sensor to the SDA1/SCL1 pins instead of the SDA0/SCL0 ones, to avoid I2C detection issues.

VI. INSTALLATION:

1. Give execution permissions to the build script and execute it:
   • chmod u+x build && ./build
2. Copy the compiled plugin to the nagios plugins directory:
   • sudo cp bin/check_sht31 /usr/local/lib/nagios/plugins/check_sht31
3. Allow nagios/icinga to execute the plugin as sudo, by adding this entry to the sudoers file:
   • nagios ALL=(ALL) NOPASSWD: /usr/local/lib/nagios/plugins/check_sht31
4. Figure out from which bus you can access the sensor:
   • ls -la /dev/i2c-*
   • apt-get install i2c-tools libi2c-dev
   • sudo i2cdetect -r <bus_number> (a value of 44 should exist in the table)

VII. USAGE:

• sudo check_sht31 -b <i2c_bus_num> [-w tmp_warn_range,hum_warn_range] [-c tmp_crit_range,hum_crit_range]
  • example: sudo check_sht31 -b 1 -w 10:40,30:70 -c 5:45,25:75