首先下载mysql-5.7.18-linux-glibc2.5-x86_64.tar.gz
然后解压 tar -xvzf mysql-5.7.18-linux-glibc2.5-x86_64.tar.gz
要想好 datadir 和basedir两个路径。
我把这个压缩包，解压后，重名为为mysql，放在 /opt/mysql
然后/opt/mysql/下面有个bin文件
bin/mysqld --initialize --user=mysql --basedir=/opt/mysql --datadir=/opt/mysql_data_file/
执行完了，会出现一个临时密码，一定要记住这个临时密码：
[hadoop@Master mysql]$ sudo bin/mysqld --initialize --user=mysql --basedir=/opt/mysql --datadir=/opt/mysql_data_file/
2018-10-25T06:48:28.899955Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2018-10-25T06:48:29.467625Z 0 [Warning] InnoDB: New log files created, LSN=45790
2018-10-25T06:48:29.645286Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2018-10-25T06:48:29.786048Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: fb628d21-d821-11e8-8cdc-005056b20471.
2018-10-25T06:48:29.804129Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
2018-10-25T06:48:29.804705Z 1 [Note] A temporary password is generated for root@localhost: >xHYOl:s<6V7
如果要装ssl，那么紧接着要执行下面这一步：
bin/mysql_ssl_rsa_setup --basedir=/opt/mysql --datadir=/opt/mysql_data_file/
将mysql进程放入系统进程中，命令如下：
先修改这个support-files/mysql.server，把里面的basedir和datadir都改一下。
然后
cp support-files/mysql.server /etc/init.d/mysqld如果my.cnf 不存在，可以直接复制别人的my.cnf过来。改下对应参数。
启动 sudo /etc/init.d/mysqld restart
第一次root账号进去，会要求你改密码：
alter user 'root'@'localhost' identified by 'zhelishinizijishezhidexinmima';
参考：
生成pem ：https://www.cnblogs.com/mysql-dba/p/7061300.html 安装mysql:http://www.bubuko.com/infodetail-2164257.html
注意，如果感觉装得不对，可以重来的，很简单，就是把datadir下面的都清除（都删掉），
然后重新执行
bin/mysqld --initialize --user=mysql --basedir=/opt/mysql --datadir=/opt/mysql_data_file/
要注意basefile 和 datafile的所有者必须是mysql，经常要执行
chown -R mysql:mysql /opt/files/mysql
chown -R mysql:mysql /opt/files/mysql_data_file
还有，
use user;
select * from user where user='root';
update user set password_expired ="NO" where user='root';
