허용아이피가 어떻게 되는지 확인

select host from user where user='root';

모든 아이피 허용. 

insert into user (host,user,password) values ('%','root',password('패스워드'));
grant all privileges on *.* to 'root'@'%';
flush privileges;

ip대역으로 허용.

insert into user (host,user,password) values ('555.501.%','root',password('패스워드'));
grant all privileges on *.* to 'root'@'555.501.%';
flush privileges;

특정아이피 허용

insert into user (host,user,password) values ('555.501.502.18','root',password('패스워드'));
grant all privileges on *.* to 'root'@'555.501.502.18';
flush privileges;

원래상태로 복원

delete from mysql.user where host='%' and user='root';
flush privileges;