2022.07.02 CentOS8 上搭建Mysql 5.7

一、资源下载

Mysql 5.7 国内镜像下载地址

下载 ： mysql-5.7.37-linux-glibc2.12-x86_64.tar.gz

二、安装

1、解压：

tar -xzvf mysql-5.7.37-linux-glibc2.12-x86_64.tar.gz 

2、创建mysql 软件要存放的文件夹

mkdir /usr/local/mysql

3、移动解压文件到文件夹，并删除空文件夹

cd /usr/local
mv mysql-5.7.37-linux-glibc2.12-x86_64/* /usr/local/mysql
rmdir mysql-5.7.37-linux-glibc2.12-x86_64

4、创建数据目录

mkdir  /usr/local/mysql/data

5、查看组和用户情况

cat /etc/group | grep mysql
cat /etc/passwd |grep mysql

若存在，则删除原mysql用户,会删除其对应的组和用户:
userdel -r mysql


创建mysql组和mysql用户:
groupadd mysql
useradd -r -g mysql mysql

授权：
chown -R mysql:mysql /usr/local/mysql
chown -R mysql:mysql /var/log

6、修改配置文件：/etc/my.cnf，配置不对的话,后面初始化不全,会拿不到默认密码

vim /etc/my.cnf

[mysqld]
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
port = 3306
socket=/tmp/mysql.sock

symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/tmp/mysqld/mysqld.pid
sql_mode='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION'
[client]
default-character-set=utf8

[mysql]
default-character-set=utf8

[mysqld]
log-bin=mysql-bin 
binlog-format=ROW 
server_id=1 
max_connections=1000

init_connect='SET collation_connection = utf8_unicode_ci'
init_connect='SET NAMES utf8'
character-set-server=utf8
collation-server=utf8_unicode_ci
skip-character-set-client-handshake
explicit_defaults_for_timestamp=true

7、添加 mysql.sock 和 mysqld.pid

cd /tmp
touch mysql.sock
chown mysql:mysql mysql.sock
chmod 755 mysql.sock

创建文件/tmp/mysqld/mysqld.pid：
mkdir mysqld
cd mysqld
touch mysqld.pid
cd ..
chown -R mysql:mysql mysqld
cd mysqld
chmod 755 mysqld.pid

8、初始化数据库

cd /usr/local/mysql/bin
./mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data


安全启动:
./mysqld_safe --user=mysql &

默认密码在mysqld.log日志里, 找到后保存到安全的地方:
cat /var/log/mysqld.log

查找下面的语句：!0dt6dXvZb5q 是密码
A temporary password is generated for root@localhost: !0dt6dXvZb5q

9、登陆数据并更改密码：

cd /usr/local/mysql/bin/
./mysql -u root -p
mysql登录报错：mysql: error while loading shared libraries: libncurses.so.5: cannot open shared object file: No such file or directory

执行下面命令：
yum install libncurses*

更改默认密码
set password=password("xsd2018");
设置远程登录权限
grant all privileges on *.* to 'root'@'%' identified by 'xsd2018'; 
立即生效:
flush privileges;

10、设置开机启动

cp -a /usr/local/mysql/support-files/mysql.server /etc/init.d/mysql
查看mysql服务是否在服务配置中
chkconfig --list mysql
若没有，则把mysql注册为开机启动的服务，然后在进行查看
chkconfig --add mysql
chkconfig --list mysql

启动 或 停止
service mysql start
service mysql stop

11、设置或者关闭防火墙

• 查看防火状态

systemctl status firewalld
service  iptables status

• 暂时关闭防火墙

systemctl stop firewalld
service  iptables stop

• 永久关闭防火墙

systemctl disable firewalld
chkconfig iptables off

• 重启防火墙

systemctl enable firewalld
service iptables restart  

• 永久关闭后重启

chkconfig iptables on