check_dht22

I. DESCRIPTION:

DHT22 Sensor nagios plugin for Single Board Computers

Copyright (c) 2017 Frostbyte frostbytegr@gmail.com

Check environment temperature and humidity with DHT22 via GPIO

II. CREDITS:

• projects@drogon.net - wiringPi library and rht03 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 80
  • Humidity: from 0 to 100
• Output validation against the sensor's checksums and documented capabilities
  • If measured data are invalid, will retry every 2 seconds for a maximum of 4 times

IV. SUPPORTED DEVICES:

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

V. GPIO HEADER PINOUT

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_dht22 /usr/local/lib/nagios/plugins/check_dht22
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_dht22

VII. USAGE:

• sudo check_dht22 -p <gpio_pin> [-w tmp_warn_range,hum_warn_range] [-c tmp_crit_range,hum_crit_range]
  • example: sudo check_dht22 -p 7 -w 10:40,30:70 -c 5:45,25:75