Run the below given commands to install ioncube in ubuntu linux

1) Chnage directory to /usr/local/

cd /usr/local/

2) Download ionCube loaders

wget http://downloads.ioncube.com/loader_downloads/ioncube_loaders_lin_x86.tar.gz

3) Extract the file

tar zxvf ioncube_loaders_lin_x86.tar.gz

4) Add reference to your php.ini file

a) Chnage sirectory to apache2

cd /etc/php5/apache2/

b) Make sure that you have the back up of php.ini file

sudo cp php.ini php.ini.bck

c) Edit the php.ini file and add the referance

sudo gedit php.ini

zend_extension = /usr/local/ioncube/ioncube_loader_lin_5.2.so

5) Restart apache

/etc/init.d/apache2 restart