ESC云服务器下的Centos7环境安装MySQL5数据库

1. 运行以下命令更新YUM源。

   rpm -Uvh  http://dev.mysql.com/get/mysql57-community-release-el7-9.noarch.rpm
   

2. 运行以下命令安装MySQL。

   说明 如果您使用的操作系统内核版本为el8，可能会提示报错信息No match for argument。您需要先运行命令yum module disable mysql禁用默认的MySQL模块，再安装MySQL。

   yum -y install mysql-community-server --nogpgcheck
   

3. 运行以下命令查看MySQL版本号。

   mysql -V
   

   返回结果如下所示，表示MySQL安装成功。

   mysql  Ver 14.14 Distrib 5.7.31, for Linux (x86_64) using  EditLine wrapper
   

4. 运行以下命令启动MySQL。

   systemctl start mysqld
   

5. 依次运行以下命令设置开机启动MySQL。

   systemctl enable mysqld
   systemctl daemon-reload
   

6. 运行以下命令查看MySQL的初始密码。

   grep "password" /var/log/mysqld.log
   

   返回结果示例如下，本示例中初始密码为+47,uijcojcU。

   2020-08-28T03:01:49.848762Z 1 [Note] A temporary password is generated for root@localhost: +47,uijcojcU
   

7. 运行以下命令配置MySQL的安全性。

   mysql_secure_installation
   

   安全性的配置包含以下五个方面：

   1. 重置root账号的密码。

      说明 请您安全保管root账号的密码信息。

      Enter password for user root: #输入上一步获取的root用户初始密码。The existing password for the user account root has expired. Please set a new password.New password: #输入新密码，长度为8至30个字符，必须同时包含大小写英文字母、数字和特殊符号。特殊符号可以是()` ~!@#$%^&*-+=|{}[]:;‘<>,.?/Re-enter new password: #重复输入新密码。The 'validate_password' plugin is installed on the server.The subsequent steps will run with the existing configurationof the plugin.Using existing password for root.Estimated strength of the password: 100Change the password for root ? ((Press y|Y for Yes, any other key for No) :Y #按Y，并再次输入上步已设置的密码。New password: #再次输入新密码。Re-enter new password: #重复输入新密码。Estimated strength of the password: 100Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) :Y #按Y使用新密码。
      

   2. 输入Y删除匿名用户账号。

      By default, a MySQL installation has an anonymous user,
      allowing anyone to log into MySQL without having to have
      a user account created for them. This is intended only fortesting, and to make the installation go a bit smoother.
      You should remove them before moving into a production
      environment.
      
      Remove anonymous users? (Press y|Y for Yes, any other key for No) : Y  #是否删除匿名用户，输入Y
      Success.
      

   3. 输入Y禁止root账号远程登录。

      Normally, root should only be allowed to connect from'localhost'. This ensures that someone cannot guess atthe root password from the network.
      
      Disallow root login remotely? (Press y|Y for Yes, any other key for No) : Y #禁止root远程登录，输入Y
      Success.
      

   4. 输入Y删除test库以及对test库的访问权限。

      By default, MySQL comes with a database named 'test' that
      anyone can access. This is also intended only for testing,and should be removed before moving into a production
      environment.
      
      Remove test database and access to it? (Press y|Y for Yes, any other key for No) : Y #是否删除test库和对它的访问权限，输入Y
       - Dropping test database...
      Success.
      
       - Removing privileges on test database...
      Success.
      

   5. 输入Y重新加载授权表。

      Reloading the privilege tables will ensure that all changesmade so far will take effect immediately.Reload privilege tables now? (Press y|Y for Yes, any other key for No) : Y #是否重新加载授权表，输入YSuccess.All done!
      

        安装完之后：使用navicat进行登录，如果访问不了报以下错误：1130,"Host 'xx' is not allowed to connect to this MySQL server" 

使用：mysql -uroot -p进行登录，进入到数据库后输入下面命令行，

GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '你的登录密码' WITH GRANT OPTION;

然后刷新就可以访问了

如果没有反应可以使用flush privileges 命令进行刷新

刷新权限是指在MySQL中用来刷新权限的命令，主要用于重新加载用户权限。该命令格式如下：

FLUSH PRIVILEGES;