一、【使用网易源安装 MySQL】

1.1 CentOS 7 安装MySQL

(2020-11-17 发现网易yum镜像不能用了，清华可以)

添加yum 源文件： vi /etc/yum.repos.d/mysql-community.repo

[mysql-connectors-community]

name=MySQL Connectors Community

baseurl=https://mirrors.163.com/mysql/yum/mysql-connectors-community-el7-$basearch/

enabled=1

gpgcheck=1

gpgkey=https://repo.mysql.com/RPM-GPG-KEY-mysql

[mysql-tools-community]

name=MySQL Tools Community

baseurl=https://mirrors.163.com/mysql/yum/mysql-tools-community-el7-$basearch/

enabled=1

gpgcheck=1

gpgkey=https://repo.mysql.com/RPM-GPG-KEY-mysql

[mysql-5.6-community]

name=MySQL 5.6 Community Server

baseurl=https://mirrors.163.com/mysql/yum/mysql-5.6-community-el7-$basearch/

enabled=0

gpgcheck=1

gpgkey=https://repo.mysql.com/RPM-GPG-KEY-mysql

[mysql-5.7-community]

name=MySQL 5.7 Community Server

baseurl=https://mirrors.163.com/mysql/yum/mysql-5.7-community-el7-$basearch/

enabled=1

gpgcheck=1

gpgkey=https://repo.mysql.com/RPM-GPG-KEY-mysql

[mysql-8.0-community]

name=MySQL 8.0 Community Server

baseurl=https://mirrors.163.com/mysql/yum/mysql-8.0-community-el7-$basearch/

enabled=1

gpgcheck=1

gpgkey=https://repo.mysql.com/RPM-GPG-KEY-mysql

安装mysql：yum install mysql-community-server

1.2 CentOS 8 或 6 安装 MySQL

只需将上面repo脚本中所有 el7 替换成 el8 或 el6 即可。

sed -i 's#el7#el8#g' /etc/yum.repos.d/mysql-community.repo # Centos 8

sed -i 's#el7#el6#g' /etc/yum.repos.d/mysql-community.repo # Centos 6

1.3 安装指定版本

以v5.7为例：将上面脚本中除 ‘mysql-5.7-community’ 标签下 enabled = 1，其他标签下全部置为0即可。

二、【使用其他国内源】

2.1 使用清华源

直接将上面脚本域名换成 mirrors.tuna.tsinghua.edu.cn 即可。

sed -i 's#mirrors.163.com#mirrors.tuna.tsinghua.edu.cn#g' /etc/yum.repos.d/mysql-community.repo

2.2 使用腾讯源

替换域名为 mirrors.cloud.tencent.com

sed -i 's#mirrors.163.com#mirrors.cloud.tencent.com#g' /etc/yum.repos.d/mysql-community.repo

三、安装后初始化

3.1 启动服务

systemctl start mysqld

systemclt enable mysqld

systemctl daemon-reload

3.2 修改初始密码

- 从日志中获取系统初始密码

grep 'generated' /var/log/mysqld.log | awk -F ' ' '{print $13}'

- 使用初始密码登录并修改初始密码

mysql -uroot -p

alter user 'root'@'localhost' identified by 'Admin@123';

- 修改密码安全级别策略

在配置文件 /etc/my.cnf中添加：

validate_password.length = 0

validate_password.mixed_case_count = 0

validate_password.number_count = 0

validate_password.policy = LOW

validate_password.special_char_count = 0

现在可以重新登录mysql修改简单密码或空密码了。

3.3 开启远程连接

有些远程客户端不支持 caching_sha2_password 密码加密方式，改成native 方式:

// 允许root任意ip登录

update user set host='%' where user='root';

flush privileges;

// 修改密码加密方式

alter user 'root'@'%' identified with mysql_native_password by '123456';

// 设置root 密码永久有效

alter user 'root'@'%' identified by '123456' password expire never;

flush privileges;