先去官网下载RPM包，没想到RPM包是红帽发行版
https://dev.mysql.com/downloads/mysql/
使用wget直接下载到Centos里面：
wget https://cdn.mysql.com//Downloads/MySQL-8.0/mysql-8.0.27-1.el7.x86_64.rpm-bundle.tar
解压Tar包：
[root@localhost ~]# tar -xvf mysql-8.0.27-1.el7.x86_64.rpm-bundle.tar mysql-community-client-8.0.27-1.el7.x86_64.rpm mysql-community-client-plugins-8.0.27-1.el7.x86_64.rpm mysql-community-common-8.0.27-1.el7.x86_64.rpm mysql-community-devel-8.0.27-1.el7.x86_64.rpm mysql-community-embedded-compat-8.0.27-1.el7.x86_64.rpm mysql-community-libs-8.0.27-1.el7.x86_64.rpm mysql-community-libs-compat-8.0.27-1.el7.x86_64.rpm mysql-community-server-8.0.27-1.el7.x86_64.rpm mysql-community-test-8.0.27-1.el7.x86_64.rpm [root@localhost ~]#
删除残留的MariaDB
[root@localhost ~]# rpm -qa|grep mariadb mariadb-libs-5.5.68-1.el7.x86_64 [root@localhost ~]# rpm -e --nodeps mariadb-libs-5.5.68-1.el7.x86_64 [root@localhost ~]#
二次检查：
[root@localhost ~]# rpm -qa|grep mariadb [root@localhost ~]#
开始安装：
rpm -ivh --nodeps --force mysql-community-common-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-libs-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-libs-compat-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-client-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-client-plugins-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-embedded-compat-8.0.27-1.el7.x86_64.rpm rpm -ivh --nodeps --force mysql-community-server-8.0.27-1.el7.x86_64.rpm
查看我们安装的内容：
[root@localhost ~]# rpm -qa | grep mysql mysql-community-libs-8.0.27-1.el7.x86_64 mysql-community-server-8.0.27-1.el7.x86_64 mysql-community-client-plugins-8.0.27-1.el7.x86_64 mysql-community-libs-compat-8.0.27-1.el7.x86_64 mysql-community-embedded-compat-8.0.27-1.el7.x86_64 mysql-community-common-8.0.27-1.el7.x86_64 mysql-community-client-8.0.27-1.el7.x86_64 [root@localhost ~]#
查看当前MySQL服务状态：
[root@localhost ~]# systemctl status mysqld
● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
Active: inactive (dead)
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
[root@localhost ~]#
不管MySQL是否运行还是不运行，都执行服务停止命令
[root@localhost ~]# service mysqld stop Redirecting to /bin/systemctl stop mysqld.service [root@localhost ~]#
执行初始化：
[root@localhost ~]# mysqld --initialize --console [root@localhost ~]#
目录可写权限赋予：
[root@localhost ~]# chown -R mysql:mysql /var/lib/mysql/ [root@localhost ~]#
启动MySQL：
[root@localhost ~]# systemctl start mysqld [root@localhost ~]#
查看服务状态：
[root@localhost ~]# systemctl status mysqld
● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
Active: active (running) since 日 2021-10-24 09:31:18 CST; 3s ago
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
Process: 9201 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)
Main PID: 9241 (mysqld)
Status: "Server is operational"
CGroup: /system.slice/mysqld.service
└─9241 /usr/sbin/mysqld
10月 24 09:31:04 localhost.localdomain systemd[1]: Starting MySQL Server...
10月 24 09:31:18 localhost.localdomain systemd[1]: Started MySQL Server.
[root@localhost ~]#
翻看日志文件，找到初始化的密码：
[root@localhost ~]# cat /var/log/mysqld.log 2021-10-24T01:29:47.674319Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.27) initializing of server in progress as process 8984 2021-10-24T01:29:47.888787Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started. 2021-10-24T01:29:50.370284Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended. 2021-10-24T01:29:54.018924Z 0 [Warning] [MY-013746] [Server] A deprecated TLS version TLSv1 is enabled for channel mysql_main 2021-10-24T01:29:54.022463Z 0 [Warning] [MY-013746] [Server] A deprecated TLS version TLSv1.1 is enabled for channel mysql_main 2021-10-24T01:29:54.293689Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: SoOu?/jep09> 2021-10-24T01:31:13.997176Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.27) starting as process 9241 2021-10-24T01:31:14.148958Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started. 2021-10-24T01:31:15.775588Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended. 2021-10-24T01:31:18.363257Z 0 [Warning] [MY-013746] [Server] A deprecated TLS version TLSv1 is enabled for channel mysql_main 2021-10-24T01:31:18.381048Z 0 [Warning] [MY-013746] [Server] A deprecated TLS version TLSv1.1 is enabled for channel mysql_main 2021-10-24T01:31:18.383717Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed. 2021-10-24T01:31:18.383752Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel. 2021-10-24T01:31:18.586545Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.27' socket: '/var/lib/mysql/mysql.sock' port: 3306 MySQL Community Server - GPL. 2021-10-24T01:31:18.586771Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/run/mysqld/mysqlx.sock [root@localhost ~]#
登陆MySQL，输入随机生成的密码：【SoOu?/jep09>】
[root@localhost ~]# mysql -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 8 Server version: 8.0.27 Copyright (c) 2000, 2021, Oracle and/or its affiliates. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql>
设置root用户密码永不过期：
ALTER USER 'root'@'localhost' IDENTIFIED BY 'password' PASSWORD EXPIRE NEVER;
更改root密码为123456：
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';
设置root账户允许被外部访问：
UPDATE `user` SET host = "%" WHERE user = "root";
刷新权限：
FLUSH PRIVILEGES;
退出：
QUIT;
防火墙拦截处理：
先查看防火墙状态：
[root@localhost ~]# systemctl status firewalld
● firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
Active: active (running) since 日 2021-10-24 09:55:25 CST; 5s ago
Docs: man:firewalld(1)
Main PID: 12734 (firewalld)
CGroup: /system.slice/firewalld.service
└─12734 /usr/bin/python2 -Es /usr/sbin/firewalld --nofork --nopid
10月 24 09:55:23 localhost.localdomain systemd[1]: Starting firewalld - dynamic firewall daemon...
10月 24 09:55:25 localhost.localdomain systemd[1]: Started firewalld - dynamic firewall daemon.
10月 24 09:55:26 localhost.localdomain firewalld[12734]: WARNING: AllowZoneDrifting is enabled. This is considered an insecure configuration option. It will be removed in a future release. Please consider disabling it now.
[root@localhost ~]#
防火墙开启，没开放端口，会被拦截下来：
查看开放的端口列表：
[root@localhost ~]# firewall-cmd --zone=public --list-ports [root@localhost ~]#
开放3306端口：
[root@localhost ~]# firewall-cmd --zone=public --add-port=3306/tcp --permanent success [root@localhost ~]#
重新加载防火墙：
[root@localhost ~]# firewall-cmd --reload success [root@localhost ~]#