robin@SZDB:~/dba_scripts/custom/bin> more ck_fs_space.sh
#!/bin/bash
# ------------------------------------------------------------------------------+
#                  CHECK FILE SYSYTEM SPACE BY THRESHOLD                        |
#   Filename: ck_fs_space.sh                                                    |
#   Desc:                                                                       |
#       The script use to check file system space by threshold                  |
#       Once usage of the disk beyond the threshold, a mail alert will be sent. |  
#       Deploy it by crontab. e.g. per 15 min                                   | 
#   Usage:                                                                      |
#       ./ck_fs_space.sh <percent> </filesystem [/filesystem2]>                 | 
#                                                                               |
#   Author : Robinson                                                           |
#   Blog   :http://blog.csdn.net/robinson_0612                                 |
# ------------------------------------------------------------------------------+
#
# -------------------------------
#  Set environment here
# ------------------------------

if [ -f ~/.bash_profile ]; then
    . ~/.bash_profile
fi

export host=`hostname`
export mail_dir=/users/robin/dba_scripts/sendEmail-v1.56
exportmail_list='Robinson.cheng@12306.com'
exportmail_fm='oracle@szdb.com'
tmpfile=/tmp/ck_fs_space.txt
alert=n

# --------------------------------
#  Check the parameter
# --------------------------------

max=$1

if [ ! ${2} ]; then
    echo "No filesystems specified."
    echo "Usage: ck_fs_space.sh 90 / /u01"
    exit 1
fi

# --------------------------------
#  Start to check the disk space
# --------------------------------

while [ "${2}" ]
    do
        percent=`df -P ${2} | tail -1 | awk '{print $5 }' | cut -d'%' -f1`
        if [ "${percent}" -ge "${max}" ]; then
            alert=y
            break
        fi;
        shift
    done;

# ------------------------------------------------------------------------
#  When a partition was above the threshold then send mail with df output
# ------------------------------------------------------------------------

if [ ! "${alert}" = 'n' ];then
    df -h >$tmpfile
    mail_sub="Disk usage beyond the threshold ${max} on ${host}."
    $mail_dir/sendEmail -u ${mail_sub} -f $mail_fm -t $mail_list -o message-file=${tmpfile}
fi;

exit;