Version tags should be used only for questions that apply to a version only, not to merely say what version a site is using.
Drupal 7 is the Drupal version that was officially released on January 5, 2011.
Use this tag only if your question relates specifically to this version.
Drupal 7's minimum requirements are the following ones:
- Disk space: 15 Megabytes
- Web server: Apache 1.3, Apache 2.x, or Microsoft IIS
- Database server: MySQL 5.0.15 or higher with PDO, SQLite 3.3.7 or higher Microsoft SQL Server and Oracle are supported by an additional module.
- PHP: PHP 5.2.5 or higher (5.3 recommended)
- The standard PHP extensions (enabled by default) Hash and JSON are required for Drupal version 7.
- Drupal 7 Update manager can install/update modules and themes via SSH if the required libraries have been installed on the server. If you have administrator rights on a Debian/Ubuntu server, and SSH is not already available (see your phpinfo) it can usually be installed by executing:
apt-get install libssh2-php.
- PHP Data Objects (PDO) must be activated for Drupal 7 to install and run correctly. Look in your php.ini. Uncomment (remove the leading semicolon) at line
extension=php_pdo_mysql.dll. In Linux, these would be
extension=pdo_mysql.so. Some Linux distributions may have these extensions by default in files found in the conf.d folder. If these lines are not there, you will need to add them. The PECL version of PDO is not compatible with Drupal 7 and cannot be used. More information can be found on What is PDO?.
- Drupal 7 may require the time parameter to be at least 30 seconds.
Each major release of Drupal is not compatible with the previous one (hence the importance of using, wherever appropriate, the version tags).
The release specific version tags available today for the most commonly used releases are: