1. 规划

官网：MySQL 社区官网，下载包需要创建oracle账户，本地使用的是Linux 通用的二进制包mysql-8.0.31-linux-glibc2.12-x86_64.tar md5：89e902edeb75216c366e878f3c9e85be

2. MySQL 8.0.x安装过程

2.1 安装准备

groupadd mysql
useradd -r -g mysql -s /bin/false mysql # 用户不登录
# 数量路径
mkdir -p /data/mysql/data_3306
# 日志路径
mkdir -p /data/mysql/binlog_3306
cd /usr/local && xz -dc mysql-8.0.31-linux-glibc2.12-x86_64.tar.xz | tar x
ln -s mysql-8.0.31-linux-glibc2.12-x86_64 mysql
# 环境变量
vim /etc/profile
export PATH=$PATH:/usr/local/mysql/bin
source /etc/profile
# 安装依赖
apt-get install libtinfo5

which mysql
/usr/local/mysql/bin/mysql
# 授权
chown -R mysql.mysql /data/ /usr/local/mysql/

2.2 初始化

apt-get install libaio-dev
# 初始化数据库
mysqld --initialize-insecure --user=mysql --basedir=/usr/local/mysql --datadir=/data/mysql/data_3306
# 创建临时配置文件
cat > /etc/my.cnf <<EOF 
[mysqld]
user=mysql
basedir=/usr/local/mysql
datadir=/data/mysql/data_3306
socket=/tmp/mysql.sock
server_id=6
log_bin=/data/mysql/binlog_3306
port=3306
[mysql]
socket=/tmp/mysql.sock
EOF

--initialize-insecure：不安全的 , 没有密码,没有密码策略

--initialize：安全的模式,没次初始化完成都会生成临时密码,只能登陆数据库,需要人为修改后才能正常管理数据库。

2.3 准备启动文件

cp /usr/local/mysql/support-files/mysql.server  /etc/init.d/mysql
cat > /usr/lib/systemd/system/mysql.service <<EOF
#内容如下：
[Unit]
Description=MySQL
SourcePath=/etc/init.d/mysql
Before=shutdown.target

[Service]
User=mysql
Type=forking
TimeoutSec=0
PermissionsStartOnly=true
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/etc/my.cnf --user=mysql --daemonize
ExecStop=/etc/init.d/mysql stop
LimitNOFILE = 65535
Restart=on-failure
RestartSec=10
RestartPreventExitStatus=1
PrivateTmp=false

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl start mysql.service

几个systemctl常用的命令：

# 列出所有可用单元
systemctl list-unit-files

# 从可用单元中查看是否有mysql
systemctl list-unit-files | grep mysql

# 启动mysql服务
systemctl start mysql.service

# 查看mysql服务状态active即为启动状态，inactive是非启动状态
systemctl status mysql.service


# 重启mysql服务
systemctl restart mysql.service

# 停止mysql服务
systemctl stop mysql.service

附录：

# 设置密码
mysql
use mysql;
alter user 'root'@'localhost' identified by '123456';
flush privileges;
#退出重新登录
mysql -uroot -p123456