Installing Drush via Composer

Since the standard drush installation could bring to some issues, we prefer to install drush via Composer, following the steps below.

Install drush globally via composer:

$ composer global require drush/drush

Make the drush command globally available, on Mac:

$ ln -s ~/.composer/vendor/bin/drush /usr/bin/local/drush

or on Ubuntu:

$ ln -s ~/.composer/vendor/bin/drush ~/bin/drush

Check the installation:

$ drush core-status

References

http://docs.drush.org/en/master/install/
https://www.drupal.org/node/2366283
https://www.drupal.org/node/1791676
http://www.drush.org/en/master/install-alternative/