Virtualmin, by default, configures all scripts, including PHP, to execute as the owner of the virtual server account via the usage of suexec. This precludes the use of mod_php, and takes the place of hacks like suphp. Because execution of PHP as a CGI script can be slower than mod_php, Virtualmin makes use of mod_fcgid which allows PHP scripts to exist as long-running processes. This leads to PHP execution speed on par with running under mod_php while still providing a level of security only available to scripts running under suexec.

One pleasant feature of executing PHP scripts under mod_fcgid and CGI is that each user has their own private php.ini, which can be configured in any way that makes sense for the scripts the user is executing. Given that many scripts have requirements that can adversely effect security, it is of great value in a virtual hosting environment, but it also imposes additional complexity on the system and administrator. In general, Virtualmin maintains the php.ini files and the administrator need never think of them, but there are instances where manual configuration is required.

Individual php.ini files are stored in $HOME/etc/php.ini, and can be administered using the PHP Configuration module found under the Services menu under each domain within Virtualmin. As with all configuration files under Virtualmin, it is also safe to modify the files directly using your favorite text editor.

Note: Changing /etc/php.ini will not effect changes in the php.ini of individual virtual servers, e.g. /home/mydomain.com/etc/php.ini. The php.ini of individual virtual servers have to be modified by hand, or via sed or similar command line editing tools, if required. There is no safe way of implementing global changes to all php.ini files. On some systems, there is an /etc/php.d directory, where files that are automatically included by the default php.ini. Thus, you may be able to make system-wide changes by creating a new ini file in this directory containing your directives.

As mentioned, since the php.ini files are all independently maintained when using mod_fcgid and CGI, updating the whole system to use some new php.ini directive can be a time-consuming process. The Virtualmin command line tools can make that process painless.

A common change is to increase the memory_limit from the default 8M to something a bit more reasonable like 32M. To do that using the Virtualmin command line tools, for all virtual servers, you could execute:

virtualmin modify-php-ini --all-domains --ini-name memory_limit --ini-value 32M

You have to get a little fancier to append whole sections to php.ini. One way to do that is using the cat command and what is known as a here document.

For example, to append a Zend section to all top-level (e.g. /home/domain/etc/php.ini) php.ini files, one could execute something like the follow:

cat <<EOF >> /home/*/etc/php.ini
[Zend]
zend_extension_manager.optimizer=/usr/local/Zend/lib/Optimizer-3.2.6
zend_extension_manager.optimizer_ts=/usr/local/Zend/lib/Optimizer_TS-3.2.6
zend_optimizer.version=3.2.6
zend_extension=/usr/local/Zend/lib/ZendExtensionManager.so
zend_extension_ts=/usr/local/Zend/lib/ZendExtensionManager_TS.so
 

Note: The Zend section is very specific to your environment and version. Do not copy this verbatim, as it will be wrong for your system and Zend!

Virtualmin, Inc. maintains an unsupported repository of bleeding edge versions of some software that is occasionally version dependent, PHP among them. If you'd like to use the latest released version of PHP, on your system, and understand the risks involved in running software that is dramatically less well-tested and vetted (for security, stability, and performance) than the version provided by your OS, and a repository for your OS is available, it can be used to get the latest features of PHP.

We do not recommend use of the Virtualmin bleeding edge repository, for PHP or otherwise. But, if you need the latest version of anything, we recommend you get it from our repository rather than building from source or obtaining it from other sources (which are likely to be even less well-tested, compatible, and concerned with security).

Read more about the Virtualmin Bleeding Edge Packages.