MariaDB [(none)]> grant all privileges on *.* TO tank@'192.168.%' IDENTIFIED BY 'test'; 

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO) 

MariaDB [(none)]> show grants\G; 

*************************** 1. row *************************** 
Grants for root@localhost: GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, SHUTDOWN, PROCESS, FILE, REFERENCES, INDEX, ALTER, SHOW DATABASES, SUPER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, REPLICATION SLAVE, REPLICATION CLIENT, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT, TRIGGER ON *.* TO 'root'@'localhost' WITH GRANT OPTION 
1 row in set (0.00 sec) 
 
ERROR: No query specified 

mysql> show grants; 

+---------------------------------------------------------------------+ 
| Grants for root@localhost | 
+---------------------------------------------------------------------+ 
| GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION | 
+---------------------------------------------------------------------+ 
1 row in set (0.00 sec) 

MariaDB [(none)]> grant all on test.* TO tank@'192.168.%' IDENTIFIED BY 'test'; 

Query OK, 0 rows affected (0.00 sec) 

MariaDB [(none)]> grant select on *.* TO tank@'192.168.%' IDENTIFIED BY 'test'; 

Query OK, 0 rows affected (0.00 sec)