bash script to alert via pushover if disk free percentage falls before a certain amount on a particular device [change DevMon var to a different variable to use something different]. Tested on readynas 516

df-pushoveralert.sh

#! /usr/bin/env bash
let notify=75
let criticalnotify=91
let doAct=0
DevMon="/dev/md0"
let percval=`df -h | grep -i $DevMon |  awk '{ print +$5 }'`
echo percval = $percval
echo notify = $notify
sSev="INFO"
##check for critical warning -- can be disabled by making $criticalnotify a crazy number 
if [ $percval -ge $criticalnotify ]; then
      echo "we should notify as CRITICAL as $percval is  gte than $criticalnotify"
      let doAct=2
      #critical notify
      sSev="CRIT"
      echo "Sending Pushover using curl with $sSev"
      curl -s \
                -F "token=<API-Token-APP>" \
                -F "user=<API-Token-User>" \
                -F "title=DiskFree Alert sev: $sSev" \
                -F "priority=$doAct" \
                -F "retry=180" \
                -F "priority=$doAct" \
                -F "retry=180" \
                -F "sound=siren" \
            	-F "expire=3620" \
                -F "message=DiskFree Perc: $percval" \
     http://api.pushover.net/1/messages > /dev/null
fi
### handle warning level -- seperated to allow different alerting sources or actions
elif [ $percval -ge $notify ]; then
       echo "we should notify as $percval is  gte than $notify"
       let doAct=1
       sSev="WARN"
else
       echo no notification needed $percval less than $notify
fi

echo doAct =  $doAct
echo "magic severity = $sSev ... DOACT = $doAct" 
if [ $sSev == "WARN"  ] ; then 
	echo "normal severity messsge going out"
	echo "Sending Pushover using curl with $sSev"
	curl -s \
        	-F "token=<API-Token-APP>" \
        	-F "user=<API-Token-User" \
        	-F "title=DiskFree Alert sev: $sSev" \
		-F "priority=$doAct" \
        	-F "message=DiskFree Perc: $percval" \
        http://api.pushover.net/1/messages > /dev/null

fi