IonCube is a commonly used PHP “Loader” open-source software that provides a stable known PHP environment for your PHP based websites.
IonCube install requires a config update and a rebuild of your cPanel Apache web server software and is started by entering the ‘EasyApache (Apache Update)’ pages from the ‘WHM Home’ -> ‘Software’ link.
At the first page you can usually just click the “Start Customising based on profile” button (at the bottom of that page) and progress through your Easy:Apache pages until you get to Step 4, the ‘4. Short Options List’ page and tick and select the ‘IonCube Loader for PHP’ button, then click the ‘Save and Build’ button at the bottom of the page.
This build process takes a while and please be sure that your browser stays running until it finishes, but once that rebuild is done, you can enable IonCube via logging into your WHM site as root, select the ‘Server Configuration’ menu and the ‘Tweak Settings’ page, then click the ‘PHP’ tab and at the bottom, select ‘ioncube’ as the “cPanel PHP loader” and click the ‘Save’ button there.
FYI and regards,