Shell Programming and Scripting

Some times my disk space is used upto 100% due to the application logs .

So this script is to monitor the disk space usage and wall message to the users about the disk space usage if it exceeds the limit set in the script. Here for example the limit is set to 80%. This job is added in cron to execute in a time frame.

I am using this on solaris machines . You can adopt it on any unix/linux machine.

Code:

#!/bin/ksh
# This script checks the percentage of disk usuage and  walls messages if its greater then 80%
typeset -i error="80"
if [ -e diskusage.txt ]; 
then
rm diskusage.txt 
fi
if [ -e diskusage1.txt ];
then
rm diskusage1.txt 
fi
for disc in `df -h| egrep '^/dev' | egrep -iv 'cdrom|proc|sys|pts' |awk '{print $6}'`
do
  /usr/sbin/df -h $disc| cut -c46-47|grep -i [1-9] >> diskusage1.txt 
discUsage=`cat diskusage1.txt `
rm diskusage1.txt 
if [ "$discUsage" -ge "$error" ];
then
echo "Disc usage for $disc is at $discUsage%" >> diskusage.txt 
fi
done
if [ -e diskusage.txt ]; 
then
message=`cat diskusage.txt` 
fi
if [ ${#message} -gt 0 ]; 
then
  cat diskusage.txt | wall
fi

Even i want to add a small script for monitor space

Code:

home/l> space
                         SPACE OF IMPORTANT FILE SYSTEMS
------------------------------------------------------------------------
FILE-SYSTEM        TOTAL-SPACE     USED-SPACE      FREE-SPACE      %USED

/home                   4.75            2.23            2.52         47%
/outputs               32.00           15.27           16.73         48%
/backup                60.00           40.42           19.58         68%
/fns                   60.00           47.68           12.32         80%
/var                    5.00            3.04            1.96         61%
-------------------------------------------------------------------------
Color Significance for USED spaces:   gt-80 %  lt-80 % & gt-40 %  lt-40 %

Code:

home/> cat space
df -gt /tmp /home /outputs /backup /fns /var|awk 'BEGIN{
print "\t\t\t\033[1;43m SPACE OF IMPORTANT FILE SYSTEMS\t\033[m\n------------------------------------------------------------------------\n\033[1;45mFILE-SYSTEM \t TOTAL-SPACE \t USED-SPACE \t FREE-SPACE \t %USED\033[m\n"}
function disp(color_code,v1,v2,v3,v4,v5){
printf "\033[1;"color_code"m%-10s\t%10s\t%10s\t%10s\t%6s\033[m\n",v1,v2,v3,v4,v5
}
NR>2&&(($3>($2*.80)&&disp(31,$6,$2,$3,$4,$5))||($3>($2*.40)&&$3<($2*.80)&&disp(33,$6,$2,$3,$4,$5))||($3<($2*.40)&&disp(32,$6,$2,$3,$4,$5)))
END{print "-------------------------------------------------------------------------\nColor Significance for USED spaces:   \033[1;31mgt-80 % \033[m \033[1;33mlt-80 % & gt-40 %\033[m \033[1;32m lt-40 %\033[m"}'

How about:


#!/bin/sh

#############################################################################
# This script is for monitoring disk usage and for alerting when the disk
# usage exceed certain percentage usage values. It will run continously.
#
# For each filesystem tobe monitored, you can specify up to 5 threshold
# values. The way the script works is that when the first threshold is hit,
# an alert is sent. A second alert is only sent if the second threshold is
# hit.
#
# Please note that the max alerts allowed is reset if the script if ever
# stopped and restarted.
#############################################################################

#
# This how often the disk usage will be examined. This value is in minutes
#
DISK_USAGE_CHECK_INTERVAL_MINS=5

#
# This is a comma separate list of email addresses that will be notified
# when we have a situation requiring a notification
#
NOTIFICATION_TARGETS=lstorm2003@yahoo.com,jsfinis@yahoo.com

#
# These are the filesystems to be monitored and their threshold values. each
# record contains a colon separated fields as follows:
#
# <file_system_name>:<t1>:<t2>:<t3>:<t4>:<t5>:<max_alerts>
#
# You must specify all 5 threshold values as percentages. If you want
# to use less than 5 different percentages, you can use the same value multiple
# times.
#
# <max_alerts> is used to specify the maximum number of alerts that would be
# sent out for a filesystem threshold issue. If this is -1, then there will
# be no maximum. Even though there are just 5 threshold values, if the
# 5th threshold is hit, then we would alert everytime as long as we haven't
# exceeded the <max_alerts> setting
#
# Here are some examples and how they would work:
#
# /home:90:92:94:96:98:5
# This will generate the first alert once we hit 90%. Subsequent
# alerts will only be sent when we hit 92%, 94%, 96%, and 98%
# respectively. We will only send 5 alerts even if we continue
# to remain above 98%
#
# /home:90:92:94:94:94:-1
# This will generate the first alert once we hit 90%. The
# next alert will only be sent when we hit 92%. From that point
# forward, once we go above 94% we will continue to send alerts
# indefinitely
#
cat << EOF > vrdiskmon.fs
/home:90:92:94:96:98:5
/home/dtdb23in:90:92:94:96:98:5
/opt/sapdb:90:92:94:96:98:5
/var/vvt:90:92:94:96:98:5
/var:90:92:94:96:98:5
/home/dtdb23in:90:92:94:96:98:5
/db2translog:90:92:94:96:98:5
/opt/sapdb:90:92:94:96:98:5
/var/vvt:90:92:94:96:98:5
/opt/vsuite:90:92:94:96:98:5
EOF

#############################################################################
# All customizations should occur above here. Nothing below here was #
# designed to be configrable #
#############################################################################

HOSTNAME=`hostname`

FILESYSTEM_USAGE_INFO_FILE=""
FS=""
T1=""
T2=""
T3=""
T4=""
T5=""
MAX_ALERTS=""

NUM_ALERTS_SENT=""
LAST_THRESHOLD_USED=""
LAST_USAGE=""

THESHOLD_VALUE_TO_CHECK_AGAINST=""
THRESHOLD_NUMBER_BEING_USED=""



#
# Get the current usage percentage for the given filesystem. This function
# takes a single parameter, the filesystem name. The method
# returns the percentage usage. The invoker of the function would get
# this by checking "$?"
#
getCurrentUsage()
{
_USAGE=`df -k | grep $1 | grep -v "$1/" | # Find the filesystem
tr -s ' ' | # Collapse whitespace
cut -d' ' -f4 | # Get the 4th field
sed 's/%//g'` # Strip the '%' symbol

return $_USAGE
}


#
# Get the last usage info from the specified file. This function takes a
# single parameter, the filename. It then fills in the following
# variables: NUM_ALERTS_SENT, LAST_THRESHOLD_USED, and LAST_USAGE. If there
# is no file which is the case if we never hit a threshold value, then these
# variables get filled in with zeros
#
getLastUsageInfo()
{
NUM_ALERTS_SENT="0"
LAST_THRESHOLD_USED="0"
LAST_USAGE="0"

if (test -f "$1") then
NUM_ALERTS_SENT=`grep NUM_ALERTS_SENT $1 |
cut -d'=' -f2`
LAST_THRESHOLD_USED=`grep LAST_THRESHOLD_USED $1 |
cut -d'=' -f2`
LAST_USAGE=`grep LAST_USAGE $1 |
cut -d'=' -f2`
else
return
fi
}

saveLastUsageInfo()
{
rm -f $1
echo "NUM_ALERTS_SENT=$NUM_ALERTS_SENT" >> $1
echo "LAST_THRESHOLD_USED=$LAST_THRESHOLD_USED" >> $1
echo "LAST_USAGE=$LAST_USAGE" >> $1
}


#
# Get the name of the file we'll use to hold info about a filesystem. The
# name of the file is based on the filename name and stored in /tmp. The
# filename is returned in the variable FILESYSTEM_USAGE_INFO_FILE
#
getUsageInfoFilename()
{
_SAFE_FS_NAME=`echo $1 | sed 's/\//_/g'`
FILESYSTEM_USAGE_INFO_FILE="/tmp/vrdiskmon.$_SAFE_FS_NAME.info"
}


#
# Get he next threshold value to be used for checking the disk usage.
# This takes a single parameter, the last threshold number that was used. It
# sets the variables THESHOLD_VALUE_TO_CHECK_AGAINST and
# THRESHOLD_NUMBER_BEING_USED
#
getNextThresholdToUse()
{
THESHOLD_VALUE_TO_CHECK_AGAINST=""
THRESHOLD_NUMBER_BEING_USED=""

case $LAST_THRESHOLD_USED in
0)
THESHOLD_VALUE_TO_CHECK_AGAINST=$T1
THRESHOLD_NUMBER_BEING_USED=1
;;
1)
THESHOLD_VALUE_TO_CHECK_AGAINST=$T2
THRESHOLD_NUMBER_BEING_USED=2
;;
2)
THESHOLD_VALUE_TO_CHECK_AGAINST=$T3
THRESHOLD_NUMBER_BEING_USED=3
;;
3)
THESHOLD_VALUE_TO_CHECK_AGAINST=$T4
THRESHOLD_NUMBER_BEING_USED=4
;;
*)
THESHOLD_VALUE_TO_CHECK_AGAINST=$T5
THRESHOLD_NUMBER_BEING_USED=5
;;
esac
}

#
# Take a record of the filesystem to be checked and the threshold values
# and parse it. The results are placed in the variables: FS, T1, T2, T3, T4,
# T5, and MAX_ALERTS.
#
parseFilesystemRecord()
{
FS=`echo $1 | cut -d: -f1`
T1=`echo $1 | cut -d: -f2`
T2=`echo $1 | cut -d: -f3`
T3=`echo $1 | cut -d: -f4`
T4=`echo $1 | cut -d: -f5`
T5=`echo $1 | cut -d: -f6`
MAX_ALERTS=`echo $1 | cut -d: -f7`

if (test $MAX_ALERTS -lt 0) then
MAX_ALERTS=999999
fi
}


#
# Send an alert. This function expects the following arguments:
# - The filesystem
# - The current usage
# - The last usage
#
sendAlert()
{
ALERT_MSG=/tmp/vrdiskmon.alert

if (test $3 -eq 0) then
STATUS_MSG="$HOSTNAME: $1 at $2%."
else
STATUS_MSG="$HOSTNAME: $1 at $2%. Previous: $3%"
fi

echo "To: $NOTIFICATION_TARGETS" >> $ALERT_MSG
echo "Subject: $STATUS_MSG" >> $ALERT_MSG
echo "" >> $ALERT_MSG
date >> $ALERT_MSG
echo "$STATUS_MSG" >> $ALERT_MSG

sendmail $NOTIFICATION_TARGETS < $ALERT_MSG
rm -f $ALERT_MSG
}


#
# Remove any old usage data before starting
#
rm -f /tmp/vrdiskmon.*.info > /dev/null 2>&1

while (true) do
echo " "
echo " "
cat vrdiskmon.fs |
while (true) do
read line
if (test "$line" = "") then
break
fi

parseFilesystemRecord $line

# Get the current usage
getCurrentUsage $FS
CURRENT_USAGE=$?

getUsageInfoFilename $FS

if (test $CURRENT_USAGE -lt $T1) then
echo "The current usage of [$CURRENT_USAGE] for [$FS] is below the lowest threshold of [$T1]"

# Since we are below the alerting threshold, remove any previous
# info we may have so we can start the "checking" with a clean
# slate
rm -f $FILESYSTEM_USAGE_INFO_FILE

else
getLastUsageInfo $FILESYSTEM_USAGE_INFO_FILE
getNextThresholdToUse $LAST_THRESHOLD_USED

if (test $CURRENT_USAGE -ge $THESHOLD_VALUE_TO_CHECK_AGAINST) then
echo " "
echo "FileSystem=[$FS], currentUsage=[$CURRENT_USAGE] usageFile=[$FILESYSTEM_USAGE_INFO_FILE]"
echo " LAST USAGE: numAlertsSent=[$NUM_ALERTS_SENT] lastThresholdUsed=[$LAST_THRESHOLD_USED] lastUsage=[$LAST_USAGE]"

if (test $NUM_ALERTS_SENT -lt $MAX_ALERTS) then
echo "Sending an alert for filesystem [$FS]"

sendAlert $FS $CURRENT_USAGE $LAST_USAGE

NUM_ALERTS_SENT=`expr $NUM_ALERTS_SENT + 1`
else
echo "Reached the maximum number of alerts. Alert NOT sent"
fi

LAST_USAGE=$CURRENT_USAGE
LAST_THRESHOLD_USED=$THRESHOLD_NUMBER_BEING_USED
else
echo "The usage of [$CURRENT_USAGE] for filesystem [$FS] has not exceeded the next threshold value of [$THESHOLD_VALUE_TO_CHECK_AGAINST]"
fi

saveLastUsageInfo $FILESYSTEM_USAGE_INFO_FILE

fi
done

# Sleep
SLEEP_INTERVAL_SECS=`expr $DISK_USAGE_CHECK_INTERVAL_MINS \* 60`
echo "Sleeping for $DISK_USAGE_CHECK_INTERVAL_MINS minutes ($SLEEP_INTERVAL_SECS seconds)"
sleep $SLEEP_INTERVAL_SECS

done