Install ioncube-loader on centOS 64bit

ioncube loaders are available for 32 bit and 64 bit system both.
Suppose you are using 64 bit Linux system (CentOs, Fedora, Ubuntu or Debian).

Download 64 bit ioncube loader zip file from

http://downloads2.ioncube.com/loader_downloads/ioncube_loaders_lin_x86-64.tar.gz

Extract it and Put the directory in your htdocs, Now run

http://localhost/ioncube/loader-wizard.php

There are number of ioncube .so files in the ioncube directory because you may have different version of php. When you run the wizard, it shows required .so file which you should use, copy your required ioncube.so file and put it in /usr/lib64/php/modules (for centOS 64 bit) 

Add following line at bottom of the line [php] in the file php.ini

zend_extension = /usr/lib64/php/modules/ioncube_loader_lin_5.4.so

Restart httpd, and run

http://localhost/ioncube/loader-wizard.php

you will get
The ionCube Loader version 4.6.1 for PHP 5.4 is already installed and encoded files should run without problems.

If you restart httpd and check the status,if it says
httpd dead but subsys locked
 
It means zend_extension is somewhere defined in the ini file, comment the line, restart httpd and it will be running.