mysql客户端授权后连接失败问题

在本地（192.168.1.152）部署好mysql环境，授权远程客户机192.168.1.%连接本机的mysql，在iptables防火墙也已开通3306端口。
如下：
mysql> select host,user,password from mysql.user;
+--------------+-----------------+---------------------------------------------------------+
| host              | user                 | password                                                                  |
+--------------+-----------------+----------------------------------------------------------+
| localhost       | root                 |                                                                                  |
| fdm1            | root                 |                                                                                  |
| 127.0.0.1     | root                 |                                                                                  |
| localhost       |                        |                                                                                  |
| fdm1 | | |
| 192.168.1.% | db_hqsb         | *DFC9DC16B13651A95ECEC3A26E07D244431B55C9 |
| 192.168.1.% | db_ro_hqsb    | *2C0B0DD50595BB40879110437BEEF026D019DFB7 |
| 192.168.1.% | db_jkhwuser   | *2C0B0DD50595BB40879110437BEEF026D019DFB7 |
| 192.168.1.25| slave               | *EE52B8EACB3CCD13624273AD6B5CDA52B9B53EB7 |
| 192.168.1.% | tech_db_user  | *6053E57C7B61043DC2C6B4E3291D5F61CCC23F5C |
| 192.168.1.% | game_db_user| *05EA4D71C9A1273ECF3E24E6323F7175AE45C366  |
| localhost        | zabbix            | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9  |
+---------------+---------------+------------------------------------------------------------+

问题：
在客户机（比如192.168.1.20）上远程连接上面192.168.1.152机器的mysql，连接失败！
[root@huanqiu ~]# mysql -udb_ro_hqsb -h 192.168.1.152 -pmhxzkhl0802xqsjdb
ERROR 1130 (HY000): Host '192.168.1.20' is not allowed to connect to this MySQL server

解决：
是由于192.168.1.152的mysql里“host为localhost，user和password为空”这条语句导致的，删除这条即可解决问题！

mysql> delete from mysql.user where host="localhost" and user="";
Query OK, 1 row affected (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

这样，授权连接的客户机就能成功连接了！
[root@huanqiu ~]# mysql -uxqsj_db_ro_user -h 192.168.1.152 -pmhxzkhl0802xqsjdb
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 28
Server version: 5.1.73 Source distribution

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