由于mysql 5.7版本以后 support_files文件夹中无 my_default.cnf 文件，所以今天给大家详细描述一下 mysql 5.7版本的安装步骤，本次安装mysql提供两种安装方法。

yum安装

卸载系统自带MySQL

• 检查服务中是否有自带的mysql，如果有就remove

  yum list installed|grep mysql
  yum -y remove mysql-libs.x86_64

下载安装MySQL高版本源

• 源的下载你可以去官网下载，也可以去清华源下载。个人比较喜欢清华源

  wget https://mirrors.tuna.tsinghua.edu.cn/mysql/yum/mysql57-community-el7/mysql57-community-release-el7-10.noarch.rpm
  yum localinstall mysql57-community-release-el7-10.noarch.rpm
  # 检查mysql源是否安装成功
  yum repolist enabled | grep "mysql.*-community.*"

安装MySQL

• 安装

  yum install mysql-community-server
  # 检查mysql是否安装成功
  rpm -qa|grep mysql

• 启动MySQL

  systemctl start mysqld

• 修改MySQL的root的密码

  # 查看yum安装MySQL默认密码
  grep localhost /var/log/mysqld.log 
  # 进入MySQL数据库
  mysql -uroot -p默认密码
  - mysql> set global validate_password_policy=0;
  - mysql> set password=password('your passwd');

二进制包部署

下载并解压二进制包

cd /usr/local/src/
wget https://mirrors.tuna.tsinghua.edu.cn/mysql/downloads/MySQL-5.7/mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz
tar zxvf mysql-5.7.26-linux-glibc2.12-x86_64.tar.gz

创建用户和所需目录

useradd mysql
touch /var/log/mysqld.log
chmod 777 !$
chown mysql:mysql !$
cd /usr/local/mysql
mkdir data
chmod 777 ../mysql/
chown mysql:mysql !$

修改my.cnf配置文件

vim /etc/my.cnf

# 删除里面的所有内容添加下面的内容
[client]
port = 3306
socket = /tmp/mysql.sock

[mysqld]
character_set_server=utf8
init_connect='SET NAMES utf8'
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
socket=/tmp/mysql.sock
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
#不区分大小写
lower_case_table_names = 1

sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

max_connections=5000

default-time_zone = '+8:00'

初始化数据库

/usr/local/mysql/bin/mysqld --initialize --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --lc_messages_dir=/usr/local/mysql/share --lc_messages=en_US

配置MySQL服务启动脚本并加入系统变量

cp support-files/mysql.server /etc/init.d/mysqld
chmod +x /etc/init.d/mysqld
chkconfig --add mysqld 
chkconfig --level 345 mysqld on
export PATH=$PATH:/usr/local/mysql/bin

启动MySQL并修改密码

/etc/init.d/mysqld start
# 如果启动的时候出现提示 Starting MySQL.. ERROR! The server quit without updating PID file (/var/run/mysqld/mysqld.pid).
# 执行如下命令
mkdir /var/run/mysqld/
touch /var/run/mysqld/mysqld.pid
chmod 777 /var/run/mysqld/mysqld.pid
chown mysql:mysql !$
/etc/init.d/mysqld start

修改MySQL的root密码

# 查看yum安装MySQL默认密码
grep localhost /var/log/mysqld.log 
# 进入MySQL数据库
mysql -uroot -p默认密码
- mysql> set global validate_password_policy=0;
- mysql> set password=password('your passwd');