Script DiskFree para Linux

#!/bin/bash
THRESHOLD="20"
EMAIL="user@empresa.com.br"

df -P | awk '{print $6"\t"$5}' |grep "%" | while read LINE; do
PERC=`echo $LINE |awk '{print $2}' |cut -d"%" -f1`
if [ $PERC -gt $THRESHOLD ]; then
   echo "ALERT $LINE UTILIZADO em `hostname`" | /bin/mail -s "Disk Space Alert: ${LINE} used on `hostname`" $EMAIL
fi
done
#