CentOS 安装 MySQL8，超详细！

```text
rpm -ev mysql80-community-release-el7-7.noarch
rpm -ev mysql-community-client-plugins-8.0.22-1.ky3.kb1.x86_64
```

下载地址：[MySQL :: Download MySQL Community Server (Archived Versions)](https://link.zhihu.com/?target=https%3A//downloads.mysql.com/archives/community/)

注：版本需对应，如下述包都是8.0.32

```text
mysql-community-client-8.0.32-1.el7.x86_64.rpm
mysql-community-client-plugins-8.0.32-1.el7.x86_64.rpm
mysql-community-common-8.0.32-1.el7.x86_64.rpm
mysql-community-icu-data-files-8.0.32-1.el7.x86_64.rpm
mysql-community-libs-8.0.32-1.el7.x86_64.rpm
mysql-community-server-8.0.32-1.el7.x86_64.rpm
```

### **4\. 按依赖顺序安装**

将下载好的rpm包拷至服务器，可按下列顺序安装，或按提示安装

```text
rpm -ivh mysql-community-client-plugins-8.0.32-1.el7.x86_64.rpm 
rpm -ivh mysql-community-common-8.0.32-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.32-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.32-1.el7.x86_64.rpm
rpm -ivh mysql-community-icu-data-files-8.0.32-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.32-1.el7.x86_64.rpm
```

### **5\. 重启mysql服务**

```text
systemctl start mysqld.service
```

### **6\. 检查mysql服务运行状态**

```text
systemctl status mysqld.service
```

### **7\. 停止mysql服务**

```text
systemctl stop mysqld.service
```

### **8\. 重启mysql服务**

```text
systemctl restart mysqld.service
```

## **二、MySQL修改密码及登录**

### **1\. 获取初始密码**

```text
grep 'temporary password' /var/log/mysqld.log
```

### **2\. 登录mysql**

```text
# -h ip地址
mysql -u root -p
```

输入上述命令获取的密码

### **3\. 修改密码**

```text
ALTER USER 'root'@'localhost' IDENTIFIED BY 'PASSWD';
```

### **4\. 查看mysql密码策略**

```text
SHOW VARIABLES LIKE 'validate_password%';
```

### **5\. 设置密码安全等级为LOW**

```text
set global validate_password.policy=LOW;
```

### **6\. 设置密码长度为6**

```text
set global validate_password.length=6;
```

### **7\. 修改密码**

```text
ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
```

### **8\. 添加新用户**

```text
CREATE USER 'username'@'host' IDENTIFIED BY 'password';
```

## **三、设置mysql允许远程登录**

### **1\. 改表法**

```text
use mysql;
select host, user from user;
update user set host = '%' where user = 'root';
```

### **2\. 授权法（未验证）**

```text
use mysql;
select  User,authentication_string,Host from user;
GRANT ALL PRIVILEGES ON *.* TO 'username'@'%' IDENTIFIED BY 'password' WITH GRANT OPTION;
FLUSH PRIVILEGES;
```

### **3\. 重启服务生效**

```text
systemctl restart mysqld.service
```

### **4\. 注意**

本教程为测试环境，出于安全性考虑，在生产运行环境下应做到：

-   不应当给root用户开启远程登录权限。
-   给用户赋权时，应当根据用户的需求，做到权限细分。如限定登录的ip地址，在grant命令中只开放select、update的权限等。

## **四、开启关闭服务器防火墙**

### **1\. 查看服务器防火墙是否开启**

```text
# 如果显示running，则为开启状态
firewall-cmd --state
```

### **2\. 关闭防火墙**

```text
systemctl stop firewalld.service
```

### **3\. 开启防火墙**

```text
systemctl start firewalld.service
```

### **4\. 关闭开机自启动**

```text
systemctl disable firewalld.service
```

### **5\. 开启开机自启动**

```text
systemctl enable firewalld.service
```