rpm -qa |grep mysql
如果不为空,则删除,有多个则删除多个
eg: rpm -e mysql-community-server-5.7.30-1.el7.x86_64
yum install wget
wget http://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm
rpm -ivh mysql80-community-release-el7-3.noarch.rpm
cd /etc/yum.repos.d/
vim mysql-community.repo
将 [mysql57-community] 下的 enabled 设置为1,表示打开5.7
将 [mysql80-community] 下的 enabled 设置为0,表示关闭8.0
yum -y install mysql-community-server
如执行上面命令报错,则先执行
yum module disable mysql
mysql --version
systemctl start mysqld.service or systemctl start mysqld 启动mysql
systemctl stop mysqld.service or systemctl stop mysqld 停止mysql
systemctl mysql mysqld.service 重启mysql
systemctl status mysqld.service 查看mysql状态
# 获取mysql临时密码
grep 'temporary password' /var/log/mysqld.log
# 登录
mysql -uroot -p
# 修改密码 密码规则:必须包含 大小写字母、数字、特殊符号
set password for 'root'@'localhost'=password('Qa2020@0825!');
# 刷新到内存
flush privileges
# 添加远程登录用户
GRANT ALL PRIVILEGES ON *.* TO 'xiao'@'%' IDENTIFIED BY 'Xiao2020@0825!' WITH GRANT OPTION
or
use mysql;
UPDATE user SET Host='%' WHERE User='root';
flush privileges #刷新
vim /etc/my.cnf
# 末尾添加
[mysqld]
character-set-server=utf8
[client]
default-character-set=utf8
[mysql]
default-character-set=utf8
重启mysql 并进入到mysql
show variables like 'character%';
# 查看防火墙端口是否开放
firewall-cmd --query-port=3306/tcp
# 开放防火墙端口3306
firewall-cmd --zone=public --add-port=3306/tcp --permanent
# 关闭防火墙
systemctl stop firewalld
# 打开防火墙
systemctl start firewalld
# 开放一段端口
firewall-cmd --zone=public --add-port=40000-45000/tcp --permanent
# 查看开放的端口列表
firewall-cmd --zone=public --list-ports