> ## Documentation Index
> Fetch the complete documentation index at: https://citodocs.prostack.host/llms.txt
> Use this file to discover all available pages before exploring further.

# PHP

> PHP configuration, versions, and extensions on Cito

This page explains how Cito's PHP setup works.

If you wish to change PHP versions for individual sites, see [Changing PHP Versions](/managing-sites/php-version).

## Overview

PHP configuration can be found in `/etc/php/<version>/fpm/pool.d/www.conf`. If you need to make ini changes please do so using this file.

We disable a small number of PHP functions that are considered to be security risks.

We use the `dynamic` PHP-FPM Process Manager and by default have a maximum of 500 child processes.

Opcache is enabled by default for performance improvements.

## Command-line PHP

It's important to note that if you're using a different PHP version in your CLI scripts you'll need to either reference that version's binary directly, or add an alias to your `bash_profile` to switch to it.

For example, if your server has a default version of PHP 7.4 but you're using PHP 8.4, you will need to invoke it at the command-line as follows:

```bash theme={null}
/usr/bin/php8.4 <command>
```

You can also add an alias for `php` to your bash\_profile as follows:

```bash theme={null}
echo "alias php='/usr/bin/php8.4'" >> ~/.bash_profile
```

(Substituting the version appropriately).

## What versions are supported?

We follow the official PHP support policies detailed on [https://www.php.net/supported-versions.php](https://www.php.net/supported-versions.php).

If you require another version please contact support.

## What extensions are enabled?

By default, the following extensions are enabled:

* bcmath
* intl
* gd
* mbstring
* cli
* common
* curl
* imap
* json
* mysql
* opcache
* xml
* zip
* readline
* soap
* redis

Contact support if you need anything else installed.

## What are the default configuration values?

These can be found below. If you need any settings to be adjusted please contact Support.

| Setting                       | Value           |
| ----------------------------- | --------------- |
| memory\_limit                 | 2048M           |
| upload\_max\_filesize         | 1024M           |
| post\_max\_size               | 1024M           |
| date.timezone                 | "Europe/London" |
| opcache.max-accelerated-files | 65406           |
| max\_execution\_time          | 18000           |
| realpath\_cache\_size         | 10M             |
| realpath\_cache\_ttl          | 7200            |
| max\_input\_vars              | 10000           |