#!/bin/bash

if ! command -v iostat &>/dev/null; then
  echo "iostat not found! Please install sysstat:"
  echo "sudo apt install sysstat"
  exit 1
fi

if [ "$1" = "-w" ] && [ "$2" -gt "0" ] && [ "$3" = "-c" ] && [ "$4" -gt "0" ]; then
  IOWAIT=$(iostat | sed -n "4p" | awk {'print $4'} | cut -d. -f1)
  if [ "$IOWAIT" -ge "$4" ]; then
    echo "IO Wait: CRITICAL - $IOWAIT % |IOWAIT=$IOWAIT;;;;"
    exit 2
  elif [ "$IOWAIT" -ge "$2" ]; then
    echo "IO Wait: WARNING - $IOWAIT % |IOWAIT=$IOWAIT;;;;"
    exit 1
  else
    echo "IO Wait: OK  - $IOWAIT % |IOWAIT=$IOWAIT;;;;"
    exit 0
  fi
else
  echo "$0 v1.0"
  echo ""
  echo "Usage:"
  echo "$0 -w <warnlevel> -c <critlevel>"
  echo ""
  echo "warnlevel and critlevel is percentage value without %"
  echo "
	echo "EXAMPLE: check_iowait -w 90 -c 95
  echo ""
  exit
fi