Shell script to watch the disk space
df displays the amount of disk space available on the file system containing each file name argument. If no file name is given, the space available on all currently mounted file systems is shown. Read man page of df if you are new to df command.
Steps
=> Find disk space using df
=> Filter out filesystem and find out the percentage of space using grep
=> Write a shell script
Step # 1: First get disk space:
$ df -H
Output:
Filesystem Size Used Avail Use% Mounted on /dev/hdb1 20G 14G 5.5G 71% / tmpfs 394M 4.1k 394M 1% /dev/shm /dev/hdb5 29G 27G 654M 98% /nas/www
Step # 2: Next filter out filesystem and find out the percentage of space
$ df -H | grep -vE '^Filesystem|tmpfs|cdrom' | awk '{ print $5 " " $1 }'
Output:
71% /dev/hdb1 98% /dev/hdb5
Step # 3: Write a shell script
Above command displays field 5 and 1 of df command. Now all you need to do is write a script to see if the percentage of space is >= 90% (download script):
#!/bin/sh
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 [ $usep -ge 90 ]; then
echo "Running out of space \"$partition ($usep%)\" on $(hostname) as on $(date)" |
mail -s "Alert: Almost out of disk space $usep%" you@somewhere.com
fi
done
Setup Cron job
Save and install script as cronjob. Copy script to /etc/cron.daily/ (script downolad link)
# cp diskAlert /etc/cron.daily/
# chmod +x /etc/cron.daily/diskAlert
OR install as cronjob:
crontab -e
Write cronjob as per your requirement
10 0 * * * /path/to/diskAlert
Updated script version
Tony contributed and updated my script - You can exclude selected filesystem in case you don't want monitor all filesystems.
#!/bin/sh
# set -x
# Shell script to monitor or watch the disk space
# It will send an email to $ADMIN, if the (free available) percentage of space is >= 90%.
# -------------------------------------------------------------------------
# Set admin email so that you can get email.
ADMIN="root"
# set alert level 90% is default
ALERT=90
# Exclude list of unwanted monitoring, if several partions then use "|" to separate the partitions.
# An example: EXCLUDE_LIST="/dev/hdd1|/dev/hdc5"
EXCLUDE_LIST="/auto/ripper"
#
#::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
#
function main_prog() {
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 server $(hostname), $(date)" | \
mail -s "Alert: Almost out of disk space $usep%" $ADMIN
fi
done
}
if [ "$EXCLUDE_LIST" != "" ] ; then
df -H | grep -vE "^Filesystem|tmpfs|cdrom|${EXCLUDE_LIST}" | awk '{print $5 " " $6}' | main_prog
else
df -H | grep -vE "^Filesystem|tmpfs|cdrom" | awk '{print $5 " " $6}' | main_prog
fi
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Tags: df_command, disk_space, filesystem, grep, grep_command, monitor_hard_disk_space, script_step, shell_script, space_available
I noticed that on devices that have very long path in some cases there might be a line break appended to the output and that will in turn create an error when the script is run like:
line 22: [: -ge: unary operator expected
To remove the line break just append “-P” to the “df” command.
example:
df -HlP
(P) = adds posix compliance to the output.
Errors that occured: df -H
/dev/mapper/volume00-pgvol
50G 31G 19G 62% /localhome/postgresql
with -P
/dev/mapper/volume00-pgvol 50G 31G 19G 62% /localhome/postgresql
Also if you only have one type of filesystem that you need to monitor then add “-t ext3″ will only show EXT3 filesystems.
Hope it helps.
Regards,
Per L
Per Lindahl,
Thanks for sharing your tip!
Please show me if I need to get disk file last week or 10 days ago, what do I need to do?
Thank you ~ Trula
For my case:
df -h | grep d30 | awk ‘{ print $5 ” ” $1 }’ | while read output;
worked better. Thanks for shell script, life saver one.
HI
thanks for script but i am getting following error
on my solaris 9 servrer after executing the scipt.
syntax error at line 5: `usep=$’ unexpected
Regards
Sorabh harit
@sorabh harit:
That is because you run a “real” Bourne shell, which doesn’t understand the syntax on that line.
Also, there is a fair bit of double code at the end, and use of a function isn’t really necessary.
I’ve put up a modified version on my site:
http://www.qwertyboy.org/files/diskspace.txt
Niek.
Can you please tell me how to find disk usage for a particular user only…!
I tried using this script but I’m getting a syntax error, trying to run this on linux(redhat as 4) any thoughts?
-bash-3.00$ ./diskscript.sh
13% /dev/cciss/c0d0p2
17% /dev/cciss/c0d0p1
1% /dev/cciss/c0d0p5
./diskscript.sh: line 4: syntax error near unexpected token `do’
./diskscript.sh: line 4: `do’
#!/bin/sh
#df -H | grep -vE ‘^Filesystem|tmpfs|cdrom’ | awk ‘{ print $5 ” ” $1 }’ | while read output;
df -F ext3 -k | grep -vE ‘^Filesystem|tmpfs|cdrom’ | awk ‘{print $5 ” ” $1}’
do
echo $output
usep=$(echo $output | awk ‘{ print $1}’ | cut -d’%’ -f1 )
partition=$(echo $output | awk ‘{ print $2 }’ )
if [ $usep -ge 90 ]; then
echo “Running out of space \”$partition ($usep%)\” on $(hostname) as on $(date)” |
mail -s “Alert: Almost out of disk space $usep%” derek@iona.com
fi
done
while executing the below script i am getting the following:
Script:
#!/bin/sh
df -H | grep -vE ‘^Filesystem’ | 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 [ $usep -ge 50 ]; then
echo “Running out of space \”$partition ($usep%)\” on $(hostname) as on $(date)” |
mail -s “Alert: Almost out of disk space $usep%” Hari-Krishna.Reddy@in.standardchartered.com
fi
done
Error:
sh diskAlert.sh
/dev/mapper/rootvg-rootvol
diskAlert.sh: line 7: [: /dev/mapper/rootvg-rootvol: integer expression expected
/ 4.2G
diskAlert.sh: line 7: [: /: integer expression expected
14% /dev/sda1
0% none
/dev/mapper/rootvg-homevol
diskAlert.sh: line 7: [: /dev/mapper/rootvg-homevol: integer expression expected
/home 2.1G
diskAlert.sh: line 7: [: /home: integer expression expected
/dev/mapper/rootvg-sharedvol
diskAlert.sh: line 7: [: /dev/mapper/rootvg-sharedvol: integer expression expected
/shared 6.3G
diskAlert.sh: line 7: [: /shared: integer expression expected
/dev/mapper/rootvg-varvol
diskAlert.sh: line 7: [: /dev/mapper/rootvg-varvol: integer expression expected
/var 2.1G
diskAlert.sh: line 7: [: /var: integer expression expected
can any one help me on this.
i want the disk space scripts where it should send the mail in the .lst file
i am able to run the shell script properly but if i put it in a crontab its not working fine
can anyone plz suggest me in this
thnks
david