In apache conf under that user add this:
<IfModule mod_security2.c>
SecRuleEngine Off
</IfModule
Restart httpd
Category: Apache
Install Zend Optimizer
cd /usr/local/src
check latest zendoptimizer
tar -zxf ZendOptimizer-3.0.1-linux-glibc21-i386.tar.gz
cd ZendOptimizer-3.0.1-linux-glibc21-i386
./install
If u still receiving “Zend Optimizer Not Installed” error page, then
SELinux is interfering with Apache’s attempt to access the .so file.
So do this commands
#chcon -t texrel_shlib_t path_of_ZendOptimizer.so (/usr/local/Zend/ZendOptimizer.so)
#execstack -c path_of_ZendOptimizer.so (/usr/local/Zend/ZendOptimizer.so)
#setenforce 0
#getenforce
then restart httpd and check.
If the issue still persist,
vi /etc/selinux/config
SELINUX=disabled
then reboot the server
cd /usr/local/src
check latest zendoptimizer
wget http://www.eth0.us/files/ZendOptimizer-3.0.1-linux-glibc21-i386.tar.gz
tar -zxf ZendOptimizer-3.0.1-linux-glibc21-i386.tar.gz
cd ZendOptimizer-3.0.1-linux-glibc21-i386
./install
If u still receiving “Zend Optimizer Not Installed” error page, then
SELinux is interfering with Apache’s attempt to access the .so file.
So do this commands
#chcon -t texrel_shlib_t path_of_ZendOptimizer.so (/usr/local/Zend/ZendOptimizer.so)
#execstack -c path_of_ZendOptimizer.so (/usr/local/Zend/ZendOptimizer.so)
#setenforce 0
#getenforce
then restart httpd and check.
If the issue still persist,
vi /etc/selinux/config
SELINUX=disabled
then reboot the server
Round Robin DNS
Round robin DNS is a technique in which load balancing is performed by a DNS server instead of a strictly dedicated machine. A DNS record has more than one value IP address.
When a request is made to the DNS server which serves this record, the answer it gives alternates for each request. For instance, if you had a three webserver that you wished to distribute requests between, you could setup your DNS zone as follows:
# vi /var/named/domain.com.db
Append/modfiy www entry:
www IN A 1.2.3.4
IN A 2.3.4.5 IN A 3.4.5.6
IN A 4.5.6.7 # /etc/init.d/named restart
When a query is made to the DNS server it will first give the IP of 1.2.3.4 for the www host. The next time a request is made for the IP of www, it will serve 2.3.4.5 and so on.
Prevent SYN attacks
1. Enable SYN cookies mechanism in the server by the executing command:
# echo 1 > /proc/sys/net/ipv4/tcp_syncookies
2. Increase the backlog queue to 2048 by the command:
# sysctl -w net.ipv4.tcp_max_syn_backlog=”2048″
Run CGI scripts anywhere in the server + Plesk
Server wide :
cd /etc/httpd/conf/
cp -p httpd.conf httpd.conf.bak
vi httpd.conf
uncomment AddHandler cgi-script .cgi
service httpd restart
or
1. create an .htaccess file in your cgi-bin directory, that file should have the following
AddType text/x-server-parsed-html .html
AddType application/x-httpd-cgi .cgi .pl
Make sure you upload it in ASCII format, not binary.
2 set the permissions on your scripts correctly.. usually to 755
Installation of Java + Apache Ant
cd /opt
mkdir java
cd java
wget http://javadl.sun.com/webapps/download/AutoDL?BundleId=29210
or
wget http://javadl.sun.com/webapps/download/AutoDL?BundleId=29214
mv jre-6u13* jre-6u13-linux-i586.bin
chmod 755 jre-6u13-linux-i586.bin
./jre-6u13-linux-i586.bin
/opt/java/jre1.6.0_13/bin/java -version
Installing Ant:
cd /opt
wget http://www.gtlib.gatech.edu/pub/apache/ant/binaries/apache-ant-1.7.1-bin.tar.gz
tar -xzf apache-ant-1.7.1-bin.tar.gz
cd apache-ant-1.7.1
export ANT_HOME=/opt/apache-ant-1.7.1
export JAVA_HOME=/opt/java/jre1.6.0_13
export PATH=${PATH}:${ANT_HOME}/bin
echo “export ANT_HOME=/opt/apache-ant-1.7.1” >> /etc/profile
echo “export JAVA_HOME=/opt/java/jre1.6.0_13” >> /etc/profile
echo “export PATH=${PATH}:${ANT_HOME}/bin” >> /etc/profile
ln -s /opt/java/jre1.6.0_13/bin/java /etc/alternatives/java
ln -s /etc/alternatives/java /usr/bin/java
Then verify the installation by:
java -version
ant -version
———————————————————————————————————–
If you are getting the following error while executing :
———————————-
ant -version
Unable to locate tools.jar. Expected to find it in /opt/java/jre1.6.0_13/lib/tools.jar
Unable to locate tools.jar. Expected to find it in /opt/java/jre1.6.0_13/lib/tools.jar
———————————-
then
cd /opt/java/jre1.6.0_13/lib/
wget 216.104.40.154/java/tools.jar
chmod 755 tools.jar
No space left on device: mod_rewrite: could not create rewrite_log_lock
If you are getting “No space left on device: mod_rewrite: could not create rewrite_log_lock” while restarting apache, then please execute the following commands in shell prompt:
ipcs -s | grep nobody
for i in `ipcs -s | grep nobody | awk ‘{print $2}’`; do ipcrm -s $i; done
Reason: Apache user occupies large number of semaphore arrays.. The above script will remove the semaphore arrays by using ipcrm command
easy apache – Premature end of script headers error
Error : BEGIN failed–compilation aborted at /var/cpanel/perl/easy/Cpanel/Easy/Utils/BackGround.pm line 12.
Compilation failed in require at (eval 18) line 3….propagated at /usr/lib/perl5/5.8.8/base.pm line 85.
Premature end of script headers: /usr/local/cpanel/whostmgr/docroot/cgi/easyapache.pl
To fix, just run:
/scripts/checkperlmodules
A Simple Rewite Rule
RewriteEngine on
RewriteCond %{HTTP_HOST} ^domainname\.com
RewriteRule ^(.*)$ http://www.domainname/$1
Script for restarting apache at load 10
#!/bin/bash
loadavg=$(uptime | awk -F “.” ‘{ print $1 }’ | awk -F “:” ‘{ print $5 }’)
if [ “$loadavg” -ge “10” ]; then
pkill -9 httpd
sleep 3
/scripts/restartsrv_httpd
fi
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