Shell Script to notify Admin if System Load is over 10

Shell Script to notify Admin if System Load is over 10


#!/bin/bash
#
# Script to notify admin user if Linux,FreeBSD load crossed certain limit
# It will send an email notification to admin.
#

# Set up limit below
NOTIFY="10.0"

# admin user email id
EMAIL="root"

# Subject for email
SUBJECT="Alert $(hostname) load average"

# -----------------------------------------------------------------

# Os Specifc tweaks do not change anything below
OS="$(uname)"
TRUE="1"
if [ "$OS" == "FreeBSD" ]; then
        TEMPFILE="$(mktemp /tmp/$(basename $0).tmp.XXX)"
    FTEXT='load averages:'
elif [ "$OS" == "Linux" ]; then
        TEMPFILE="$(mktemp)"
    FTEXT='load average:'
fi

# get first 5 min load
F5M="$(uptime | awk -F "$FTEXT" '{ print $2 }' | cut -d, -f1) | sed 's/ //g'"
# 10 min
F10M="$(uptime | awk -F "$FTEXT" '{ print $2 }' | cut -d, -f2) | sed 's/ //g'"
# 15 min
F15M="$(uptime | awk -F "$FTEXT" '{ print $2 }' | cut -d, -f3) | sed 's/ //g'"

# mail message
# keep it short coz we may send it to page or as an short message (SMS)
echo "Load average Crossed allowed limit $NOTIFY." >> $TEMPFILE
echo "Hostname: $(hostname)" >> $TEMPFILE
echo "Local Date & Time : $(date)" >> $TEMPFILE

# Look if it crossed limit
# compare it with last 15 min load average
RESULT=$(echo "$F15M > $NOTIFY" | bc)

# if so send an email
if [ "$RESULT" == "$TRUE" ]; then
        mail -s "$SUBJECT" "$EMAIL" < $TEMPFILE
fi

# remove file
rm -f $TEMPFILE