Monitor UNIX / Linux Server Disk Space with Shell Script

Shell script to monitor or watch the disk space and send an email alert if the (free avilable) percentage of space is >= 90%

#!/bin/sh
# Shell script to monitor or watch the disk space
# It will send an email to $ADMIN, if the (free avilable) percentage 
# of space is >= 90% 
# -------------------------------------------------------------------------
# Copyright (c) 2005 nixCraft project <http://cyberciti.biz/fb/>
# This script is licensed under GNU GPL version 2.0 or above
# -------------------------------------------------------------------------
# This script is part of nixCraft shell script collection (NSSC)
# Visit http://bash.cyberciti.biz/ for more information.
# ----------------------------------------------------------------------
# Linux shell script to watch disk space (should work on other UNIX oses )
# SEE URL: http://www.cyberciti.biz/tips/shell-script-to-watch-the-disk-space.html
# set admin email so that you can get email
ADMIN="me@somewher.com"
# set alert level 90% is default
ALERT=90
df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{ print $5 " " $1 }' | while read output;
do
  #echo $output
  usep=$(echo $output | awk '{ print $1}' | cut -d'%' -f1  )
  partition=$(echo $output | awk '{ print $2 }' )
  if [ $usep -ge $ALERT ]; then
    echo "Running out of space \"$partition ($usep%)\" on $(hostname) as on $(date)" | 
     mail -s "Alert: Almost out of disk space $usep" $ADMIN
  fi
done
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43 comments… add one
  • charles May 28, 2010 @ 19:31

    this script seems to run but I never get an email. I tested with a simple email from the server and it came through fine. Here’s the output I get when I debug the script with bash -x (I’m a linux newbie):

    + ADMIN=me@mydomain.org
    + ALERT=20
    + df -H
    + grep /
    + grep -vE ‘^Filesystem|tmpfs|cdrom’
    + awk ‘{ print $5 ” ” $1 }’
    + read output
    ++ awk ‘{ print $1}’
    ++ cut -d% -f1
    ++ echo 54% /dev/vzfs
    + usep=54
    ++ echo 54% /dev/vzfs
    ++ awk ‘{ print $2 }’
    + partition=/dev/vzfs
    + ‘[‘ 54 -ge 20 ‘]’
    ++ hostname
    + mail -s ‘Alert: Almost out of disk space 54’ me@mydomain.org
    ++ date
    + echo ‘Running out of space “/dev/vzfs (54%)” on ip-72-XXX-XX-XYZ.ip.secureserver.net as on Fri May 28 12:28:55 PDT 2010’
    + read output

    • Charles May 28, 2010 @ 20:11

      Actually just found out it works fine. My email was down temporarily! Thanks!

  • erdenebat Nov 4, 2009 @ 7:18

    very good!! it’s my was finding script.

    • John Mathew Mar 24, 2010 @ 6:00

      Hi,

      I have the following script;

      #!/bin/ksh
      ADMIN=”me@somewhere.com”
      # set alert level 90% is default
      ALERT=80
      df | grep -E “Filesystem|tmpfs|cdrom” | awk ‘{ print $5 ” ” $1 }’ | while read output;
      do
      #echo $output
      usep=$(echo $output | awk ‘{ print $1}’ | cut -d’%’ -f1 )
      partition=$(echo $output | awk ‘{ print $2 }’ )
      if [ $usep -ge $ALERT ]; then
      echo “Running out of space \”$partition ($usep%)\” on $(hostname) as on $(date)” |
      mail -s “Alert: Almost out of disk space $usep” $ADMIN
      fi
      done

      While I run the script it gives the following error, please help me. I have named the file as x.ksh and also let me know how to run the script.
      Thanks.

      • d0rk Jul 27, 2011 @ 23:46

        you are using the korn shell, which has many differences from bash. first off, to use parameter substitution in that shell you need:

        echo -e "string with backslash \n"
  • Stephen Adams Jun 15, 2009 @ 0:03

    Hi there,

    Nice script. I modified it in the following way for my company

    #!/bin/bash
    
    #admin email account
    ADMIN="admin@company.com"
    
    # set usage alert threshold
    THRESHOLD=40
    
    #hostname
    HOSTNAME=$(hostname)
    
    #mail client
    MAIL=/usr/bin/mail
    
    # store all disk info here
    EMAIL=""
    
    for line in $(df -hP | egrep '^/dev/' | awk '{ print $6 "_:_" $5 }')
    do
    	
    	part=$(echo "$line" | awk -F"_:_" '{ print $1 }')
    	part_usage=$(echo "$line" | awk -F"_:_" '{ print $2 }' | cut -d'%' -f1 )
    
    	if [ $part_usage -ge $THRESHOLD -a -z "$EMAIL" ];
    	then
    		EMAIL="$(date): Running out of diskspace on $HOSTNAME\n"
    		EMAIL="$EMAIL\n$part ($part_usage%) >= (Threshold = $THRESHOLD%)"
    
    	elif [ $part_usage -ge $THRESHOLD ];
    	then
    		EMAIL="$EMAIL\n$part ($part_usage%) >= (Threshold = $THRESHOLD%)"
    	fi
    done 
    
    if [ -n "$EMAIL" ];
    then 
    	echo -e "$EMAIL" | $MAIL -s "Alert: Partition(s) almost out of diskspace on $HOSTNAME" "$ADMIN"
    fi
    
    • 🐧 Vivek Gite Jun 15, 2009 @ 5:37

      Thanks for sharing the code. I’ve updated your post with pre tags.

  • john May 5, 2009 @ 14:34

    what if your both partitions will run out of space? you will receive 2 mails. if you have more partitions, then you will receive more mails. how you do to receive all messages in one mail?

    • 🐧 Vivek Gite May 6, 2009 @ 19:14

      You can modify script as follows:

      #!/bin/bash
      ADMIN="me@somewher.com"
      # set alert level 90% is default
      ALERT=90
      # store all disk info here
      DISKS="/tmp/out.df.$$"
      echo "Running out of space on $(hostname) as on $(date)" > $DISKS
      echo "" >> $DISKS
      EMAIL=0
      df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{ print $5 " " $1 }' | while read output;
      do
        #echo $output
        usep=$(echo $output | awk '{ print $1}' | cut -d'%' -f1  )
        partition=$(echo $output | awk '{ print $2 }' )
        if [ $usep -ge $ALERT ]; then
      	echo "*** $partition ($usep%) ***" >>$DISKS
      	EMAIL=1
        fi
      done
      
      [ "$EMAIL" == "1" ] && mail -s "Alert: Almost out of disk space $usep" $ADMIN < $DISKS
      
  • Todd Allis Mar 25, 2009 @ 23:50

    Thanks! I needed to change it to “df -HP” (Thanks, John Adams!), but then it worked fine. I incorporated it into an existing email notification script.

  • John Adams Mar 10, 2009 @ 18:38

    I had a similar problem with a file system checker that I wrote.
    I found that if I did a “df -P” then the LVM filesystem output would be on a single line and I could parse it. It seems the LVM filesystem names can be rather large and end up on two lines, causing confusion to the grep command..

    • Bill Mar 11, 2010 @ 22:51

      Thanks for the LVM fixed, been searching about for that answer!

  • dharjee Mar 10, 2009 @ 14:36

    Hello

    if I ran this script on my server it showed this error:
    ./diskspace: line 23: [: /dev/mapper/system-Xraid_5.4TB: integer expression expected
    ./diskspace: line 23: [: /xraid: integer expression expected

    Please any suggestion?

    Thanx

  • hudipirlo Feb 18, 2009 @ 2:59

    hi vivik

    if this script is run on the system lvm eror occurred, example

    gareng:~ # df -h
    Filesystem Size Used Avail Use% Mounted on
    /dev/sda3 31G 2.6G 29G 9% /
    tmpfs 4.0G 8.0K 4.0G 1% /dev/shm
    /dev/sda1 134M 41M 93M 31% /boot
    /dev/mapper/vgu01-lvu01
    274G 91G 183G 34% /u01
    /dev/mapper/vghome-lvhome
    20G 288M 19G 2% /home
    /dev/mapper/vgusr-lvusr
    20G 6.6G 13G 35% /usr
    /dev/mapper/vgtmp-lvtmp
    15G 35M 15G 1% /tmp
    /dev/sdc1 30G 15G 14G 52% /source
    /dev/sdc2 491G 162G 305G 35% /oradb

    i run scripts

    gareng:~ # sh coba.sh
    coba.sh: line 11: [: /dev/mapper/vgu01-lvu01: integer expression expected
    coba.sh: line 11: [: /u01: integer expression expected
    coba.sh: line 11: [: /dev/mapper/vghome-lvhome: integer expression expected
    coba.sh: line 11: [: /home: integer expression expected
    coba.sh: line 11: [: /dev/mapper/vgusr-lvusr: integer expression expected
    coba.sh: line 11: [: /usr: integer expression expected
    coba.sh: line 11: [: /dev/mapper/vgtmp-lvtmp: integer expression expected
    coba.sh: line 11: [: /tmp: integer expression expected

    i need your help

    thanks

    hudipirlo

    • d0rk Jul 27, 2011 @ 23:43

      you cannot run this with sh … you need bash as it is a BASH script.

  • vbavbalist Feb 12, 2009 @ 8:15

    How to exact use/put this script? Can you explain please . Using Redhat enterprise

  • wah Feb 12, 2009 @ 8:04

    well done ^_^

  • Tomeu Sastre Jan 22, 2009 @ 10:52

    Magnificent script.

    I’ve seen that it has a little “bug”, because it throws an error because when doing the loop it finds a non numeric value due the header of the df command.

    To resolve it I added this command to the line
    grep / (that makes tot “grep” all that have the “/” symbols, that are relatet to volumens

    and the results is :
    df -H | grep / | grep -vE ‘^Filesystem|tmpfs|cdrom’ | awk ‘{ print $5 ” ” $1 }’

  • Carl Jan 21, 2009 @ 21:12

    I need help with this can anyone help
    1) Create a subdirectory in /tmp and move multiple file(s) specified in the script argument to that directory.
    2) Compress each of these files by calling a compression program.
    3) Move the file(s) back to the original directory (after checking if under the disk quota).
    4) Use a foreach loop to do this for each file one at a time.
    4) Perform error checking

  • FD Jan 18, 2009 @ 6:35

    The script looks simple and nice… but how to do run it on redhat? do I just put on specific folder? Cron job? please let me know..

  • Caterpillar Jan 16, 2009 @ 10:49

    Super!!

  • xiaofu Nov 25, 2008 @ 9:35

    well done!

  • adhitya christiawan nurprasetyo [dit] Nov 12, 2008 @ 2:17

    my server using another port of ssh,
    can you tell me where to modify the script?
    thank you…

  • JC Oct 15, 2008 @ 8:01

    Thanks for this excellent script !

    I would just perform a “df -HP” so it would be safer : -P for Posix display to avoid bugs with the awk.

    Cheers

  • vivek Jul 31, 2008 @ 21:43

    What kind of issues you are having with regex?

  • Eddie Jul 30, 2008 @ 14:08

    Excellent, thanks!

    I am trying to write one to monitor my Raid but having some issues with the regular expressions. Any ideas?

    Cheers

  • Amit Jun 18, 2008 @ 13:42

    Good Script

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