本实验完成以下测试需求：
需求一：验证'%'是否包含'localhost'
需求二：验证localhost和127.0.0.1分别使用的连接协议
版本：mariadb 10.1.12

一.验证'%'是否包含'localhost'
先建立帐号和授权:
MariaDB [(none)]> grant all privileges on *.* to 'lmsapps'@'%' identified by "Lms166apps";
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> exit
Bye
[apps@mvxl2972 ~]$ MySQL -ulmsapps -pLms166apps --socket=/tmp/mysql3306.sock
ERROR 1045 (28000): Access denied for user 'lmsapps'@'localhost' (using password: YES)
当只有'lmsapps'@'%'有权限时，无法登入。
MariaDB [(none)]> select user,host from mysql.user;
+---------+-----------+
| user | host |
+---------+-----------+
| lmsapps | % |
| root | 127.0.0.1 |
| root | ::1 |
| | localhost |
| root | localhost |
| | mvxl2972 |
| root | mvxl2972 |
+---------+-----------+
7 rows in set (0.00 sec)

再增加lmsapps@'localhost'用户：
MariaDB [(none)]> grant all privileges on *.* to lmsapps@'localhost' identified by 'Lms166apps';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> select user,host from mysql.user;
+---------+-----------+
| user | host |
+---------+-----------+
| lmsapps | % |
| root | 127.0.0.1 |
| root | ::1 |
| | localhost |
| lmsapps | localhost |
| root | localhost |
| | mvxl2972 |
| root | mvxl2972 |
+---------+-----------+
[apps@mvxl2972 ~]$ mysql -ulmsapps -pLms166apps --socket=/tmp/mysql3306.sock
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 28
Server version: 10.1.12-MariaDB MariaDB Server

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]>

现在能正常登入。
说明'%'是不包含'localhost'

二.验证localhost和127.0.0.1分别使用的连接协议

1.在skip_name_resolve为开启状态下：
MariaDB [(none)]> show variables like 'skip%';
+---------------------------+-------+
| Variable_name | Value |
+---------------------------+-------+
| skip_external_locking | ON |
| skip_name_resolve | ON |
| skip_networking | OFF |
| skip_parallel_replication | OFF |
| skip_replication | OFF |
| skip_show_database | OFF |

先drop用户'lmsapps'@'%'
MariaDB [(none)]> drop user 'lmsapps'@'%';
Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> exit
Bye
[apps@mvxl2972 ~]$ mysql -ulmsapps -pLms166apps -h 127.0.0.1
ERROR 1045 (28000): Access denied for user 'lmsapps'@'127.0.0.1' (using password: YES)

mysql -ulmsapps -pLms166apps -h 127.0.0.1

通过127.0.0.1连接时使用TCP/IP协议：
[apps@mvxl2972 ~]$ mysql -ulmsapps -pLms166apps -h 127.0.0.1
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 34
Server version: 10.1.12-MariaDB MariaDB Server

Copyright (c) 2000, 2016, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]> \s
--------------
mysql Ver 15.1 Distrib 10.1.12-MariaDB, for Linux (x86_64) using readline 5.1

Connection id: 34
Current database:
Current user: lmsapps@127.0.0.1
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server: MariaDB
Server version: 10.1.12-MariaDB MariaDB Server
Protocol version: 10
Connection: 127.0.0.1 via TCP/IP
Server characterset: utf8
Db characterset: utf8
Client characterset: utf8
Conn. characterset: utf8
TCP port: 3306
Uptime: 1 day 22 hours 14 min 17 sec