Each website can run with its own PHP version and its own settings, so one site can be updated without affecting the others.
Changing the PHP version for a site
Go to Sites, select the site and open it for editing. The PHP version is selected there, from the versions installed on the server.
Note that only alternative PHP versions can be switched between — these are the versions installed from the panel's own repository into /opt/. The version supplied with the operating system cannot be changed. If the version you need is not in the list, it has not been installed on the server; open a ticket and we will add it.
If Auto subdomains was enabled when the domain was created, subdomains inherit the PHP version of the main domain automatically.
Before switching to a newer version, make sure your CMS and its extensions support it. Each major PHP release removes functions that were deprecated earlier, and an out-of-date plugin can bring the site down. Take a backup first; if the site breaks, switch the version back.
Changing PHP settings
Go to Sites → PHP → Extended settings, select the variable and click Edit. The settings most often changed are:
- memory_limit — how much memory a single script may use.
- upload_max_filesize and post_max_size — the maximum size of an upload. Raise both together: an upload is also a POST request, so raising
upload_max_filesizealone has no effect. - max_execution_time — how long a script may run before it is stopped. Relevant for imports and other long operations.
- date.timezone — the time zone used by all date and time functions.
- display_errors — keep this off on a live site. Error messages shown to visitors reveal file paths and other details useful to an attacker. Use log_errors instead and read the log.
Which settings take effect
Settings exist at three levels — server, user and website — and the more specific level wins: website settings override user settings, which override the server defaults. So a value changed for one site does not affect your other sites.
In the list, the colour of a value tells you where it comes from:
- green — set in the configuration file;
- red — not set in the configuration file, taken from the PHP interpreter itself;
- blue — not defined;
- yellow — read-only: fixed at server level and not changeable from your account.
If the value you need is yellow, open a ticket and tell us which parameter and which value you need.
Undoing a change
Select the variable and click Restore: your modified value is removed and the setting reverts to the level above.
PHP extensions
If your CMS reports a missing extension rather than a wrong setting, that is a separate matter — extensions are enabled per PHP version on the server. Open a ticket with the name of the extension and the site it is needed for.
If a site stops working after a change and reverting does not help, open a ticket from your client area with the domain name and what you changed.
