一、清理旧的mysql环境

1.查看当前安装的相关包

rpm -qa|grep -i mysql
# 也可能是
rpm -qa|grep -i mariadb

2.卸载相关包及目录

rpm -e --nodeps mariadb-libs-5.5.68-1.el7.x86_64
find / -name mysql
rm -rf /usr/share/mysql /usr/lib64/mysql /etc/selinux/targeted/active/modules/100/mysql

二、安装及登录

3.下载并解压tar安装包

# 使用wget下载
wget https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.29-1.el8.x86_64.rpm-bundle.tar
tar -xvf mysql-8.0.29-1.el8.x86_64.rpm-bundle.tar

4.使用yum安装先行依赖包

yum -y install libaio
yum -y install perl
yum -y install net-tools

5.按顺序安装rpm包

rpm -ivh mysql-community-common-8.0.29-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-plugins-8.0.29-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.29-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.29-1.el7.x86_64.rpm
rpm -ivh mysql-community-icu-data-files-8.0.29-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.29-1.el7.x86_64.rpm

6.查看、启动、停止mysqld服务

systemctl status mysqld # 查看
systemctl start mysqld # 启动
systemctl stop mysqld # 停止

7.第一次登录查找临时密码（必须先启动mysql服务）

# 查找临时密码
grep "temporary password" /var/log/mysqld.log

8.使用临时密码登录，并设置新密码

# 使用临时密码登录如：OVgAh2Iwk2/r
mysql -uroot -p

-- 设置密码
alter user 'root'@'localhost' identified by 'xxx';
flush privileges;

9.设置远程登录

create user mysql@'%' identified by 'xxx';
grant all privileges on *.* to mysql@'%' with grant option;
flush privileges;