Shell Programming and Scripting

#!/bin/bash
THRESHOLD="30%"
filesystems=$(df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{print $1}')
for i in $filesystems
do
UTILIZED=$(/bin/df -k $filesystems | /usr/bin/tail -1 | /bin/awk '{print $5}')
# Compare the utilized value against the threshold:
  if [[ "$UTILIZED" > "$THRESHOLD" || "$UTILIZED" = "100%" ]]; then
        echo -e "OS|Filesystem|PctUsed\t$filesystems\t2\t$filesystems is at $UTILIZED.  Please have a sysadmin check the environment for issues."
  else
        echo -e "OS|Filesytem|PctUsed\t$filesystems\t0"
  fi

done

exit 0

df | awk -v THRESHOLD=30 '/\/dev\/sd/{if(int($5)>THRESHOLD) print $1}'

df -H
df -k

And matching sample desired output.

# df -H
Filesystem             Size   Used  Avail Use% Mounted on
/dev/sda2               11G   3.6G   6.1G  37% /
/dev/sda5               11G   6.4G   3.3G  67% /opt
/dev/sda3               11G   5.0G   4.8G  51% /var
/dev/sda1              128M    12M   110M  10% /boot
tmpfs                  4.3G      0   4.3G   0% /dev/shm

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2             9.5G  3.4G  5.7G  37% /
/dev/sda5             9.5G  6.0G  3.1G  67% /opt
/dev/sda3             9.5G  4.6G  4.4G  52% /var
/dev/sda1             122M   11M  105M  10% /boot
tmpfs                 4.0G     0  4.0G   0% /dev/shm

$ df -i .
/home                (/home      ) :  1834176 total i-nodes
                                                    116539 free i-nodes
                                                   1717637 used i-nodes
                                                      1473 % i-nodes used
$