ESP8266 Computer Monitor

ESP8266 Arduino sketch to monitor Computer reachability

Introduction

The Arduino sketch is intended to run on a ESP8266 based ESP-12E board.

There are 3 components in this project -

1. Computer that we want to monitor
2. ESP-12E board
3. IFTTT enabled smart switch (Eg. D-Link Smart Plug) that is used to power both the computer and the ESP-12E board.

All the three components are connected to internet.

The ESP-12E is used to monitor the computer. When the computer is switched off, the ESP-12E switches off the power to the computer and to itself via the IFTTT enabled smart switch.

The ESP-12E uses periodic ICMP pings to determine if the computer is up. On startup, the ESP-12E periodically polls the computer and once the computer is found to be reachable, it considers itself as armed. In armed state, the ESP-12E will continue to periodically poll the computer and if the computer goes down, it will switch off the power supply by sending a command to a DLink Smart Plug via a IFTTT Webhook.

Dependencies

1. ESP8266 Arduino Core - Install in Arduino IDE by going to Preferences and adding http://arduino.esp8266.com/stable/package_esp8266com_index.json in Additional Board Manager URLs field and then installing the pacakge by going to Sketch -> Include Library -> Manage Library. More details here.
2. TaskScheduler - Install in Arduino IDE by going to Sketch -> Include Library -> Manage Library.
3. ESP8266Ping - Download the ZIP file and install in Arduino IDE by going to Sketch -> Include Library -> Add .ZIP Library.

Configuration

Configure the sketch to suit the run environment. Parameters that must be configured by editing the sketch file -

1. SSID
2. PASSWORD
3. MONITOR_IP
4. MONITOR_DURATION_MS
5. FAIL_THRESHOLD
6. CONTROL_SERVER
7. OFF_URL

Useful Links

• https://www.arduino.cc/en/Reference/HomePage
• http://esp8266.github.io/Arduino/versions/2.3.0/doc/libraries.html
• CP2102 USB driver for ESP-12E is available here.