卸载内置环境

检查是否有mariadb和mysql服务

ps ajx |grep mariadb
ps ajx |grep mysql

停止mysql服务

systemctl stop mysqld

找到mysql安装包

rpm -qa | grep mysql

删除安装包

rpm -qa | grep mysql | xargs yum -y remove

检查

ls /etc/my.cnf

ls /var/lib/mysql/

配置官方yum源

查看环境版本

cat /etc/redhat-release

当前版本是8.2
Index of /232905
选择mysql57-community-release-el7版本
新建一个MySQL的路径

mkdir MySQL

将下载的yum源上传进来

查看系统默认支持的yum源

ls /etc/yum.repos.d/ -l

安装yum源

rpm -ivh mysql57-community-release-el7.rpm

可以支持安装mysql

查找mysql相关内容

yum list | grep mysql

mysql_72">安装mysql

先禁用mysql模块

yum module disable mysql

再开始安装mysql

yum -y install mysql-community-server

如果出现GPG问题
导入较新的密钥

rpm --import https://repo.mysql.com/RPM-GPG-KEY-mysql-2022

安装成功

检查是否安装

ls /etc/my.cnf

找到my.cnf文件

找mysql服务端的软件mysqld

which mysqld

which mysql

启动服务

systemctl start mysqld.service

查看服务

ps axj |grep mysqld

netstat -ntlp

mysql_124">登录mysql

修改配置文件

vim /etc/my.cnf

添加上一行

skip-grant-tables

重启mysql服务

systemctl restart mysqld

进入

mysql -uroot -p

mysql">show databases;

mysql">quit;

退出

设置配置文件

# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html

[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M

port=3306
character-set-server=utf8
default-storage-engine=innodb
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

skip-grant-tables

重启服务

systemctl restart mysqld

查看服务

netstat -nltp