SequelizeConnectionError: (conn=-1, no: 1130, SQLState: HY000) code example
Example: host not allowed to connect to this mysql server
mysql -u root -p
-- root password
CREATE USER 'username'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON *.* TO 'username'@'localhost' WITH GRANT OPTION;
CREATE USER 'username'@'%' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON *.* TO 'username'@'%' WITH GRANT OPTION;
FLUSH PRIVILEGES;
EXIT;