阿里云主机下安装配置mysql（适用于centos5.4，Redhat没试）

1. yum -y install mysql-server
成功最后提示：
Installed:
  mysql-server.i386 0:5.0.77-4.el5_6.6                                                              

Dependency Installed:
  mysql.i386 0:5.0.77-4.el5_6.6   perl-DBD-MySQL.i386 0:3.0007-2.el5   perl-DBI.i386 0:1.52-2.el5  

Complete!
2. vim /etc/my.cnf
old_passwords=1　 ← 找到这一行，在这一行的下面添加新的规则，让MySQL的默认编码为UTF-8
default-character-set = utf8　 ← 添加这一行

然后在配置文件的文尾填加如下语句：

[mysql]
default-character-set = utf8

3. chkconfig mysqld on 命令配置mysql随系统自启动
4.chkconfig --list mysqld 查看配置结果
mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off　 ← 如果2--5为on的状态就OK
5. /etc/rc.d/init.d/mysqld start　 ← 启动MySQL服务
6. mysql -u root　 ← 用root用户登录MySQL服务器，控制台显示：
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.0.77 Source distribution
7. set password for root@localhost=password('在这里填入root密码');　 ← 设置root密码
Query OK, 0 rows affected (0.01 sec)
set password for root@cloud=password('在这里填入root密码');　 ← 设置root密码
Query OK, 0 rows affected (0.01 sec)
set password for root@127.0.0.1=password('在这里填入root密码');　 ← 设置root密码
Query OK, 0 rows affected (0.01 sec)
8. select user,host,password from mysql.user;　 ← 查看用户信息
+------+-----------+------------------+
| user | host      | password         |
+------+-----------+------------------+
| root | localhost | 435e5b2459c49408 |
| root | cloud     | 435e5b2459c49408 |
| root | 127.0.0.1 | 435e5b2459c49408 |
|      | localhost |                  |
|      | cloud     |                  |
+------+-----------+------------------+
5 rows in set (0.00 sec
9. mysql> delete from mysql.user where user='';　 ← 删除匿名用户
Query OK, 2 rows affected (0.17 sec)
10. exit　 ← 退出MySQL服务器
11. mysql -u root　 ← 通过空密码用root登录

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)　 ← 出现此错误信息说明密码设置成功

12. mysql -u root -p　 ← 通过密码用root登录
Enter password:　 ← 在这里输入密码
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 5.0.77 Source distribution
结束