These are server-wide settings and require administrator access to the panel. If your account does not have it, open a ticket telling us which extension or which parameter you need. For settings that apply to a single site, see Choosing the PHP version and changing PHP settings in ISPmanager.
Enabling a PHP extension
- Go to Web-server settings → PHP.
- Select the PHP version you want to change — each version has its own set of extensions.
- Click Extensions.
- Find the extension in the list and enable it.
Extensions are enabled per PHP version, not per site. If a site still does not see the extension, check which version that site actually uses — enabling it for PHP 8.3 does nothing for a site running on 8.1.
Enable only what is needed. Every extension is loaded into every PHP process, taking memory and adding code that could contain vulnerabilities. Conversely, disabling an extension that a site relies on will break that site at once, so if you are unsure whether something is in use, leave it enabled.
If the extension you need is not in the list, it is not available for that PHP version on this server. Open a ticket and we will look at whether it can be added.
Changing the default PHP settings
- Go to Web-server settings → PHP and select the version.
- Click Extended settings.
- Select the variable, click Edit and enter the new value.
Use Restore to remove your change and return the variable to its default.
Values set here are the server defaults. Individual users and sites can override most of them, and the more specific level wins — so a value you set here applies only where nothing more specific has been set.
You can also control what users see: select a variable and use Display to decide whether it appears in their settings at all.
Settings worth reviewing
- memory_limit — content management systems with many extensions often need more than the stock default.
- upload_max_filesize and post_max_size — raise both together, since an upload is also a POST request.
- max_execution_time — relevant for imports and other long-running scripts.
- date.timezone — used by all date and time functions.
- display_errors — keep this off. Error output shown to visitors reveals file paths and other details useful to an attacker; use log_errors and read the log instead.
After a change
Changes to extensions and settings take effect once PHP is restarted, which the panel normally handles itself. If a change made from the command line does not appear, restart the web server.
Check the result from a site: the panel shows the values in force, and your CMS should stop reporting the missing extension or the exceeded limit.
If an extension cannot be enabled, or a setting has no effect, open a ticket from your client area with the PHP version, the extension or parameter name, and the site affected.
