Per-domain PHP Selector settings are not applied when CloudLinux Isolates is used with LiteSpeed

Issue

A domain or subdomain is configured to use a different PHP version through per-domain PHP Selector / CloudLinux Isolates, but the selected PHP version is not applied.

For example, phpinfo() still shows the main domain’s or account-level PHP version instead of the PHP version selected for the isolated domain.

Environment

• cPanel
• PHP selector
• LiteSpeed
• CloudLinux Isolates / CageFS per-domain isolation
• CloudLinux OS

Solution

CloudLinux Isolates currently supports Apache only. LiteSpeed support is planned for a future release (CLOS-4167).

To use CloudLinux Isolates with per-domain PHP Selector settings, switch the web server to Apache and use a supported PHP handler.

For Apache-based environments, also verify the general PHP Selector requirements:

1. Make sure the system PHP version is set to one of the ea-phpXX versions.
2. Disable PHP-FPM for the affected domains, because PHP Selector is not compatible with PHP-FPM.
3. Set the affected domains to Inherited in MultiPHP Manager, because MultiPHP Manager has a higher priority than PHP Selector.
4. Check that .htaccess rules do not override the selected PHP version.

If the server must continue using LiteSpeed, CloudLinux Isolates / per-domain PHP Selector cannot be used for this scenario until LiteSpeed support is released. As an alternative, use one of the existing non-Isolates methods for configuring different PHP versions per directory, if it fits the customer’s setup.

Cause

CloudLinux Isolates / per-site isolation requires a supported web server integration to determine and apply the isolated domain context. LiteSpeed is not currently supported for CloudLinux Isolates, so the per-domain PHP Selector configuration is not applied as expected.

The internal task CLOS-4167 was opened to add support for PHP website isolation with LiteSpeed.

Useful links

https://docs.cloudlinux.com/cloudlinuxos/isolates/#prerequisites