Enable remote connection

-bash-4.1$ mysql -uroot -p
Enter password:
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Your MySQL connection id is 70
Server version: 5.6.21 MySQL Community Server (GPL)

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mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY 'root';
Query OK, 0 rows affected (0.00 sec)

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

mysql>

Note: ideally, granting to a specific IP would be better.
GRANT ALL PRIVILEGES ON *.* TO 'root'@'xx.xxx.xxx.xxx' IDENTIFIED BY 'root';

Workbench Instance should not greyed out anymore

mysql> SHOW GRANTS FOR 'root'@'%';

+--------------------------------------------------------------------------------------------------------------+

| Grants for root@%                                                                                            |

+--------------------------------------------------------------------------------------------------------------+

| GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY PASSWORD '*81F5E21E35407D884A6CD4A731AEBFB6AF209E1B' |

+--------------------------------------------------------------------------------------------------------------+

1 row in set (0.00 sec)