Debian GNU/Linux installation notes
This section contains notes and hints specific to installing PHP on » Debian GNU/Linux.
Unofficial builds from third-parties are not supported here. Any bugs should be reported to the Debian team unless they can be reproduced using the latest builds from our » download area.
While the instructions for building PHP on Unix apply to Debian as well,
this manual page contains specific information for other options, such as
using either the apt or aptitude
commands. This manual page uses these two commands interchangeably.
Using APT
First, note that other related packages may be desired like
libapache-mod-php to integrate with Apache 2, and
php-pear for PEAR.
Second, before installing a package, it's wise to ensure the package list is up to date. Typically, this is done by running the command apt update.
Example #1 Debian Install Example with Apache 2
# apt install php-common libapache2-mod-php php-cli
APT will automatically install the PHP module for Apache 2 and all of its dependencies, and then activate it. Apache should be restarted in order for the changes take place. For example:
Example #2 Stopping and starting Apache once PHP is installed
# /etc/init.d/apache2 stop # /etc/init.d/apache2 start
Better control of configuration
In the last section, PHP was installed with only core modules. It's
very likely that additional modules will be desired, such as
MySQL,
cURL,
GD,
etc. These may also be installed via the apt command.
Example #3 Methods for listing additional PHP packages
# apt-cache search php # apt search php | grep -i mysql # aptitude search php
The examples will show a lot of packages including several PHP specific ones
like php-cgi, php-cli and php-dev. Determine which are needed
and install them like any other with either apt
or aptitude. And because Debian performs
dependency checks, it'll prompt for those so for example to install
MySQL and cURL:
Example #4 Install PHP with MySQL, cURL
# apt install php-mysql php-curl
APT will automatically add the appropriate lines to the
different php.ini related files like
/etc/php/7.4/php.ini,
/etc/php/7.4/conf.d/*.ini, etc. and depending on
the extension will add entries similar to extension=foo.so.
However, restarting the web server (like Apache) is required before these
changes take affect.
Common Problems
- If the PHP scripts are not parsing via the web server, then it's likely that PHP was not added to the web server's configuration file, which on Debian may be /etc/apache2/apache2.conf or similar. See the Debian manual for further details.
- If an extension was seemingly installed yet the functions are undefined, be sure that the appropriate ini file is being loaded and/or the web server was restarted after installation.
-
There are two basic commands for installing packages on Debian (and other
linux variants):
aptandaptitude. However, explaining the subtle differences between these commands goes beyond the scope of this manual.
