Run a drush command on all of your sites in a multisite

To run a drush command on all of your sites in a multisite

go to your drupal root directory ie: /var/www/html/babsondev/docroot

and then run

drush @sites user-create testuser
drush @sites user-password someuser --password="gr3@tP@$s"

this will create a user on all of your sites. To get a site list you can do

drush sa | grep -v @