Prerequisites

Before installing symfony, you need to check that your computer has everything installed and configured correctly. Take the time to conscientiously read this chapter and follow all the steps required to check your configuration, as it may save your day further down the road.

Software

First of all, you need to check that your computer has a friendly working environment for web development. At a minimum, you need a web server (Apache, for instance), a database engine (MySQL, PostgreSQL, SQLite, or any PDO-compatible database engine), and PHP 5.2.4 or later.

Command Line Interface

The symfony framework comes bundled with a command line tool that automates a lot of work for you. If you are a Unix-like OS user, you will feel right at home. If you run a Windows system, it will also work fine, but you will just have to type a few commands at the cmd prompt.

PHP Configuration

As PHP configurations can vary a lot from one OS to another, or even between different Linux distributions, you need to check that your PHP configuration meets the symfony minimum requirements.

First, ensure that you have PHP 5.2.4 at a minimum installed by using the phpinfo() built-in function or by running php -v on the command line. Be aware that on some configurations, you might have two different PHP versions installed: one for the command line, and another for the web.

Then, download the symfony configuration checker script at the following URL:

http://sf-to.org/1.2/check.php

Save the script somewhere under your current web root directory.

Launch the configuration checker script from the command line:

$ php check_configuration.php

If there is a problem with your PHP configuration, the output of the command will give you hints on what to fix and how to fix it.

You should also execute the checker from a browser and fix the issues it might discover. That's because PHP can have a distinct php.ini configuration file for these two environments, with different settings.