Linux系统yum安装Mysql

1. 使用rpm -qa | grep mysql命令，检查系统是否已经安装了mysql，如果已经安装mysql，需要先卸载。

2. 添加在线mysql源
[root@centos8 ~]# vim /etc/yum.repos.d/mysql.repo
#将下面的内容添加到mysql源
#Enable to use MySQL 8.0
[mysql80-community]
name=MySQL 8.0 Community Server
baseurl=http://repo.mysql.com/yum/mysql-8.0-community/el/8/x86_64/
enabled=1
gpgcheck=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql

3. 安装mysql
[root@centos8 ~]# yum module disable mysql -y
[root@centos8 ~]# yum install -y mysql-community-common mysql-community-libs mysql-community-client mysql-community-server mysql-community-devel

4. 在 /var/lib/mysql创建个data目录，修改/etc/my.cnf的datadir配置项
[root@centos8 ~]# mkdir /var/lib/mysql/data
[root@centos8 ~]# vim /etc/my.cnf
#将
#datadir=/var/lib/mysql
#改为：datadir=/var/lib/mysql/data
datadir=/var/lib/mysql/data

5. 启动mysql服务  (停止mysql服务的命令是：systemctl stop mysqld.service)
[root@centos8 ~]# systemctl start mysqld.service

6. 将mysql设置开机自启
[root@centos8 ~]# systemctl enable mysqld.service

7. 登录mysql的时候需要设置密码：首先生成随机密码
[root@centos8 ~]# grep 'temporary password' /var/log/mysqld.log
2021-08-09T03:47:31.125687Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: *z-eYw-iY8dF

8. 登录mysql，输入刚才生成的随机密码

9. 修改密码(新密码需设置复杂点才能修改成功)
[root@centos8 ~]# mysql -uroot -p*z-eYw-iY8dF
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'hadoop123Yw-iY8dF';

10. 设置允许远程访问，mysql增加权限：mysql库中的user表新增一条记录host为“%”，user为“root”， %表示允许所有的ip访问
[root@centos8 ~]# mysql -uroot -phadoop123Yw-iY8dF
mysql> use mysql;
mysql> UPDATE user SET `Host` = '%' WHERE `User` = 'root' LIMIT 1;
mysql> flush privileges;

11. 开放防火墙端口,允许外部访问
#开放3306端口
[root@centos8 ~]# firewall-cmd --zone=public --add-port=3306/tcp --permanent  
#重新加载防火墙规则
[root@centos8 ~]# firewall-cmd --reload

12. 测试远程访问