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RadixHosting
05-02-2007, 05:19 PM
Hello,

I'm new to this community and would like to start off by sharing one of my latest scripts with you guys. This script will keep an eye on Apache. When you get attacked or when Apache gets any weird behaviour (consuming lots of memory resulting in high server load and even server crashes, I've seen it before...). You can set limits for the amount of CPU and memory Apache may use. If it reaches this limit, it will forcefully kill and restart Apache. It will also mail you interesting information on what was going on when the script took actions.

Here it goes:



#!/bin/bash
# +----------------------------------------------------------------------------
# | chkApache.sh
# | Written for www.radixhosting.com
# |
# | - Performs a basic scan to check the Apache load
# | - Forcefully restarts Apache if necessary
# | - Sends a report to the system administrator if actions taken
# +----------------------------------------------------------------------------

################################################## #############################
# *** START OF CONFIGURATION SETTINGS ***
################################################## #############################

# The delay between integrity checks
DELAY=3s

# Minimum server load (5 min. average) for the script to run (integer value)
MIN_LOAD=4

# Maximum % CPU all httpd processes are allowed to use
MAX_CPU=90

# Maximum % memory all httpd processes are allowed to use
MAX_MEM=110

# Kill all httpd processes and restart Apache when a limit has been reached
RESTART_HTTPD=1

# Send a report to the system administrator when a limit has been reached
SEND_REPORT=1

# System administrator to send reports to
ADMIN_MAIL=root

################################################## #############################
# *** END OF CONFIGURATION SETTINGS ***
################################################## #############################

while [ 1 ]
do

if [ `cat /proc/loadavg | gawk -F "." '{ print $1 }'` -ge $MIN_LOAD ]
then
KILL=0
echo "The minimum server load has been reached, performing Apache integrity scan..."
read REACHED_CPU CUR_CPU < <(ps aux | grep httpd | grep -v grep | gawk -vlimit=$MAX_CPU '{ total+=$3 } END { if (total>limit) { print 1, total } else { print 0, total } }')
if [ $REACHED_CPU -eq 1 ]
then
echo "The CPU limit has been reached. Apache is using $CUR_CPU (limit: $MAX_CPU)."
KILL=1
else
echo "The CPU limit has NOT been reached. Apache is using $CUR_CPU (limit: $MAX_CPU)."
fi
read REACHED_MEM CUR_MEM < <(ps aux | grep httpd | grep -v grep | gawk -vlimit=$MAX_MEM '{ total+=$4 } END { if (total>limit) { print 1, total } else { print 0, total } }')
if [ $REACHED_MEM -eq 1 ]
then
echo "The memory limit has been reached. Apache is using $CUR_MEM (limit: $MAX_MEM)."
KILL=1
else
echo "The memory limit has NOT been reached. Apache is using $CUR_MEM (limit: $MAX_MEM)."
fi
if [ $KILL -eq 1 ]
then
if [ $SEND_REPORT -eq 1 ]
then
echo "Sending report to the system administrator..."
mail -s "chkApache.sh alert on `hostname`" $ADMIN_MAIL <<< cat <<EOF
************************************************** ****
chkApache.sh report
************************************************** ****

*** APACHE LOAD

CPU usage: $CUR_CPU (limit: $MAX_CPU)
Mem usage: $CUR_MEM (limit: $MAX_MEM)

*** CURRENT LOAD

`cat /proc/loadavg`

*** MEMORY STATISTICS

`free -m`

*** APACHE STATUS REPORT

`lynx -dump http://127.0.0.1/whm-server-status`

*** TOP PROCESSES LIST

`top -b -n 1`

*** NETSTAT HTTP CONNECTIONS

`netstat -a | grep :http`

*** APACHE PROCESSES

`ps aux | grep httpd`

************************************************** ****
EOF
fi
if [ $RESTART_HTTPD -eq 1 ]
then
echo "Trying to kill all httpd processes..."
COUNTER=0
while [ $COUNTER -lt 50 ]; do
killall -15 httpd
killall -9 httpd
if [ $? -ne 0 ]
then
echo "All httpd processes were killed."
COUNTER=100
else
COUNTER=`expr $COUNTER + 1`
fi
done
if [ $COUNTER -ne 100 ]
then
echo "WARNING: Failed to kill all httpd processes!"
fi
echo "Restarting httpd..."
service httpd startssl
echo "Done."
sleep 5s
fi
fi
else
echo "The minimum server load has not been reached."
fi

sleep $DELAY

done


It was written for Apache 1.3 on cPanel servers but may work on other servers as well. If not, I don't think it's hard to modify this script for your needs ;).

Thanks

casitecenter
05-12-2007, 02:42 AM
thanks man for shareing this and let us know

sfxdip
05-17-2007, 11:00 AM
thanks for sharing..

SiSHCO
01-25-2008, 05:48 PM
Thanks for codes.

williamjr
03-14-2008, 06:16 PM
Thanks for sharing this script. I was also searching something that help to avoid from weired behavior of Apache. Moreover if it will mail information about the actions of script that is very coooooool.

carloramon1
03-25-2008, 05:02 PM
thanks for sharing this awesome information keep posting like that bye :)



[CODE]
#!/bin/bash
# +----------------------------------------------------------------------------
# | chkApache.sh
# | Written for www.radixhosting.com
# |
# | - Performs a basic scan to check the Apache load
# | - Forcefully restarts Apache if necessary
# | - Sends a report to the system administrator if actions taken
# +----------------------------------------------------------------------------

################################################## #############################
# *** START OF CONFIGURATION SETTINGS ***
################################################## #############################

# The delay between integrity checks
DELAY=3s

# Minimum server load (5 min. average) for the script to run (integer value)
MIN_LOAD=4

# Maximum % CPU all httpd processes are allowed to use
MAX_CPU=90

# Maximum % memory all httpd processes are allowed to use
MAX_MEM=110

# Kill all httpd processes and restart Apache when a limit has been reached
RESTART_HTTPD=1

# Send a report to the system administrator when a limit has been reached
SEND_REPORT=1

# System administrator to send reports to
ADMIN_MAIL=root

################################################## #############################
# *** END OF CONFIGURATION SETTINGS ***
################################################## #############################

while [ 1 ]
do

if [ `cat /proc/loadavg | gawk -F "." '{ print $1 }'` -ge $MIN_LOAD ]
then
KILL=0
echo "The minimum server load has been reached, performing Apache integrity scan..."
read REACHED_CPU CUR_CPU < <(ps aux | grep httpd | grep -v grep | gawk -vlimit=$MAX_CPU '{ total+=$3 } END { if (total>limit) { print 1, total } else { print 0, total } }')
if [ $REACHED_CPU -eq 1 ]
then
echo "The CPU limit has been reached. Apache is using $CUR_CPU (limit: $MAX_CPU)."
KILL=1
else
echo "The CPU limit has NOT been reached. Apache is using $CUR_CPU (limit: $MAX_CPU)."
fi
read REACHED_MEM CUR_MEM < <(ps aux | grep httpd | grep -v grep | gawk -vlimit=$MAX_MEM '{ total+=$4 } END { if (total>limit) { print 1, total } else { print 0, total } }')
if [ $REACHED_MEM -eq 1 ]
then
echo "The memory limit has been reached. Apache is using $CUR_MEM (limit: $MAX_MEM)."
KILL=1
else
echo "The memory limit has NOT been reached. Apache is using $CUR_MEM (limit: $MAX_MEM)."
fi
if [ $KILL -eq 1 ]
then
if [ $SEND_REPORT -eq 1 ]
then
echo "Sending report to the system administrator..."
mail -s "chkApache.sh alert on `hostname`" $ADMIN_MAIL <<< cat <<EOF


Aylesworth Flemming - Marketing and Advertising Agency (http://www.thead.biz/)

Asmar
09-20-2009, 05:34 AM
Nice codes :)
Thanks for sharing.

ihostman
10-26-2009, 01:07 AM
thanks for the script radixhosting :) i was looking for such type of script which will prevent server to be overloaded...thanks again!

RH1
10-26-2009, 12:46 PM
Closing thread - expired.