1. 卸载mariadb
# 一般centos7会默认安装mariadb, 新安装的mysql8会与它造成依赖冲突，可以按下列方式进行卸载：
rpm -qa | grep mariadb
#如果出现
mariadb-libs-5.5.68-1.el7.x86_64
#执行
rpm -e mariadb-libs --nodeps
我使用的是阿里云轻量级ECS服务器,没有安装mariadb
2. 下载mysql8的rpm文件(目前这个链接是可用的)
wget https://cdn.mysql.com//Downloads/MySQL-8.0/mysql-8.0.31-1.el7.x86_64.rpm-bundle.tar
#下载完成后创建目标文件夹，将其解压
cd /opt
mkdir mysql
tar -xvf mysql-8.0.31-1.el7.x86_64.rpm-bundle.tar -C /opt/mysql
#然后会出现以下几个安装包
mysql-community-client-8.0.31-1.el7.x86_64.rpm
mysql-community-client-plugins-8.0.31-1.el7.x86_64.rpm
mysql-community-common-8.0.31-1.el7.x86_64.rpm
mysql-community-debuginfo-8.0.31-1.el7.x86_64.rpm
mysql-community-devel-8.0.31-1.el7.x86_64.rpm
mysql-community-embedded-compat-8.0.31-1.el7.x86_64.rpm
mysql-community-icu-data-files-8.0.31-1.el7.x86_64.rpm
mysql-community-libs-8.0.31-1.el7.x86_64.rpm
mysql-community-libs-compat-8.0.31-1.el7.x86_64.rpm
mysql-community-server-8.0.31-1.el7.x86_64.rpm
mysql-community-server-debug-8.0.31-1.el7.x86_64.rpm
mysql-community-test-8.0.31-1.el7.x86_64.rpm
3. 安装
yum install -y perl.x86_64
rpm -ivh mysql-community-common-8.0.31-1.el7.x86_64.rpm
rpm -ivh mysql-community-libs-8.0.31-1.el7.x86_64.rpm
rpm -ivh mysql-community-client-8.0.31-1.el7.x86_64.rpm
rpm -ivh mysql-community-server-8.0.31-1.el7.x86_64.rpm
4、安装openssl
openssl官网为https://www.openssl.org/source/,找到需要下载的openssl版本，这里选择最新 openssl-1.1.1s.tar.gz 版本
# 下载openssl
cd /usr/local
wget https://www.openssl.org/source/openssl-1.1.1s.tar.gz
如果提示 To connect to www.openssl.org insecurely, use `--no-check-certificate'.
则使用以下命令:
wget https://www.openssl.org/source/openssl-1.1.1s.tar.gz --no-check-certificate
# 安装openssl
tar -xzvf openssl-1.1.1s.tar.gz
cd openssl-1.1.1s
# 将安装文件的路径指定为/usr/local/openssl 目录
./config --prefix=/usr/local/openssl
# 在指定的 /usr/local/openssl目录下安装openssl
make && make install
# 如果openssl路径不对,也可以使用软连接
ln -s /usr/local/openssl/bin/openssl /usr/bin/openssl
# 查看openssl当前版本
openssl version
# 将openssl添加到动态库的环境变量
vim /etc/ld.so.conf
添加以下内容,然后保存退出
/usr/local/openssl/lib
# 应用配置
ldconfig /etc/ld.so.conf
5、安装gcc
如果安装openssl的时候系统提示没有gcc：未找到gcc命令 或 gcc not found / gcc not exist
这时执行：
yum install gcc
安装好后重新执行 make && make install 安装openssl
6、mysql8安装失败卸载
# 查询安装
rpm -qa | grep -i mysql
# 卸载mysql
#使用rpm -e 命令卸载mysql安装包
# 删除mysql相关的服务
chkconfig --list | grep -i mysql
chkconfig --del mysql
# 删除系统中分散的mysql文件夹
find / -name mysql
# 清空mysql相关的所有目录以及文件
rm -rf
7、启动
# 启动
systemctl start mysqld
# 查看启动状态
systemctl status mysqld
8、修改密码
# 查看初始密码
grep 'temporary password' /var/log/mysqld.log
# 使用日志中查询到的密码登录
mysql -uroot -p
# 如果需要使用简单密码,首先需要将密码修改成复杂密码
ALTER USER 'root'@'localhost' IDENTIFIED BY 'AB!@#¥%&';
# 调整MySQL8密码验证规则：
set global validate_password.policy=0;
set global validate_password.length=1;
如果不修改密码,执行上面命令会提示:
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
# 再次将密码修改成简单密码
ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
# 刷新权限
GRANT ALL PRIVILEGES ON *.* TO 'root'@'local' WITH GRANT OPTION;
FLUSH PRIVILEGES;
9、设置mysql远程连接
用软件登陆Mysql8数据库时，会报错：Authentication plugin 'caching_sha2_password' cannot be loaded。
出现这个原因是mysql8之前的版本中加密规则是mysql_native_password,而在mysql8之后,加密规则是caching_sha2_password。
解决问题方法有两种,一种是升级客户端驱动, 另一种是把mysql用户登录密码加密规则还原成mysql_native_password。简单起见我们采用第二种，修改加密规则：
1、登录Mysql：
mysql -u root -p
# 修改加密规则,
ALTER USER 'root'@'localhost' IDENTIFIED BY 'password' PASSWORD EXPIRE NEVER;
# 更新一下用户的密码
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';
2、 修改用户root的localhost为‘%’
update user set host = '%' where user = 'root' and host='localhost';
3、重置密码
alter user 'root'@'%' identified WITH mysql_native_password by '123456';
4、刷新权限
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' WITH GRANT OPTION;
FLUSH PRIVILEGES;
最后最好重启一次mysql
安装mysql经常遇到的问题
一、mysql8 error while loading shared libraries: libssl.so.10: cannot open shared object
https://vault.centos.org/centos/8/AppStream/x86_64/os/Packages/compat-openssl10-1.0.2o-3.el8.x86_64.rpm
在centos安装mysql8的过程中，提示报错mysql: error while loading shared libraries: libssl.so.10: cannot open shared object file: No such file or directory；
安装compat-openssl10-1.0.2o-3.el8.x86_64
下载地址：https://centos.pkgs.org/8/centos-appstream-x86_64/compat-openssl10-1.0.2o-3.el8.x86_64.rpm.html
rpm -ivh compat-openssl10-1.0.2o-3.el8.x86_64.rpm
