During installation, exception SessionHandler::read()

Symptom: At the last step of installing Magento 2, the following exception displays:

exception 'Exception' with message 'Warning: SessionHandler::read():
open(..) failed: No such file or directory (2) ../magento2/lib/internal/Magento/Framework/Session/SaveHandler.php on line 74'
in ../magento2/lib/internal/Magento/Framework/App/ErrorHandler.php:67

This error occurs only in code versions earlier than September 28, 2015. If you installed code dated September 29 or later, this error should not occur. For more information about configuration options for Redis, see Configure Redis. For more information about specifying Redis using the command-line installer, see the installation topic or the deployment configuration topic.

Solution:

This happens when your session.save_handler PHP parameter is set to some another session storage than files (for example, redis, memcached, and so on). This is a known issue we’re working to resolve.

Solutions:

Locate php.ini

Locate php.ini by entering the following command:

php -i | grep "Loaded Configuration File"

Typical locations follow:

  • Ubuntu: /etc/php5/cli/php.ini
  • CentOS: /etc/php.ini

Workaround

  1. As a user with root privileges, open php.ini in a text editor.
  2. Locate session.save_handler
  3. Set it in any of the following ways:

    • To comment it out:

      ;session.save_path = <path>
      
    • To set it to a file system path:

      session.save_handler = files