1.由于CentOS 的yum源中没有MysqL，需要到MysqL的官网下载yum repo配置文件。

wget http://dev.MysqL.com/get/MysqL57-community-release-el7-9.noarch.rpm

2.安装yum repo文件

rpm -ivh MysqL57-community-release-el7-9.noarch.rpm

执行完成后会在/etc/yum.repos.d/目录下生成两个repo文件MysqL-community.repo MysqL-community-source.repo

3.然后更新yum缓存

yum clean all
yum makecache

4.安装MysqL

yum install MysqL-community-client.x86_64 MysqL-community-common.x86_64 MysqL-community-devel.x86_64 MysqL-community-libs.x86_64 MysqL-community-server.x86_64

或者

rpm install MysqL-server

5.启动MysqL

service MysqLd start

6.查看初始密码

grep 'temporary password' /var/log/MysqLd.log

得到如下内容：

2016-10-28T10:36:32.369073Z 1 [Note] A temporary password is generated for root@localhost: 5Oazqgpiat!p

7.使用初始密码登录

MysqL -u root -p //回车，然后输入上一步查到的初始密码

8.更改初始密码

ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass4!';
//现在的MysqL对密码强度要求较高，需要包含大小写字母、数字和特殊字符

至此，MysqL-server安装完成