drush sql-sync fails with PHP Fatal Error drush sql-sync @devyau @stageyau returns:


  Unable to load class Drupal\Driver\Database\Drush
   PHP Fatal error:  Call to a member function dump() on a
  non-object in
  /root/.composer/vendor/drush/drush/commands/sql/sql.drush.inc on line
  275


Drush command terminated abnormally due to an unrecoverable error.                                


  Error: Call to a member function dump() on a non-object in
  /root/.composer/vendor/drush/drush/commands/sql/sql.drush.inc, line
  275
First you run this command on console. if command is run successfully after then you check your drush library, I think this is drush library problem.

Second is you can try other command like :-

drush ard