在Centos8上用原来Centos7上安装MySQL5.7的方法会安装失败，显示mysql-community-server安装错误。我们用新的方法在Centos8上安装MySQL5.7

安装MySQL

\1. 添加MySQL存储库

禁用MySQL默认的AppStream存储库：

sudo dnf remove @mysql

sudo dnf module reset mysql && sudo dnf module disable mysql

centos8没有MySQL存储库，因此我们将使用centos 7存储库。创建一个新的存储库文件。

sudo vim /etc/yum.repos.d/mysql-community.repo

将以下数据插入上面的存储库中

[mysql57-community]

name=MySQL 5.7 Community Server

baseurl=http://repo.mysql.com/yum/mysql-5.7-community/el/7/$basearch/

enabled=1

gpgcheck=0

[mysql-connectors-community]

name=MySQL Connectors Community

baseurl=http://repo.mysql.com/yum/mysql-connectors-community/el/7/$basearch/

enabled=1

gpgcheck=0

[mysql-tools-community]

name=MySQL Tools Community

baseurl=http://repo.mysql.com/yum/mysql-tools-community/el/7/$basearch/

enabled=1

gpgcheck=0

\2. 安装MySQL(这里我选择MySQL5.7)

sudo dnf --enablerepo=mysql57-community install mysql-community-server

\3. 如果安装失败,使用以下方法进行安装

先下载rpm包

wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-community-common-5.7.27-1.el6.x86_64.rpm

wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-community-libs-5.7.27-1.el6.x86_64.rpm

wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-community-client-5.7.27-1.el6.x86_64.rpm

wget https://dev.mysql.com/get/Downloads/MySQL-5.7/mysql-community-server-5.7.27-1.el6.x86_64.rpm

再安装

yum install -y mysql-community-common-5.7.27-1.el6.x86_64.rpm

yum install -y mysql-community-libs-5.7.27-1.el6.x86_64.rpm

yum install -y mysql-community-client-5.7.27-1.el6.x86_64.rpm

yum install -y mysql-community-server-5.7.27-1.el6.x86_64.rpm

\4. 下载完成后检查版本

[root@test ~]# rpm -qi mysql-community-server

Name : mysql-community-server

Version : 5.7.29

Release : 1.el7

Architecture: x86_64

Install Date: Sat 22 Feb 2020 11:04:07 AM CST

Group : Applications/Databases

Size : 801919839

License : Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved. Under GPLv2 license as shown in the Description field.

Signature : DSA/SHA1, Thu 19 Dec 2019 04:12:40 PM CST, Key ID 8c718d3b5072e1f5

Source RPM : mysql-community-5.7.29-1.el7.src.rpm

Build Date : Wed 18 Dec 2019 09:31:48 PM CST

Build Host : loki02.no.oracle.com

Relocations : (not relocatable)

Packager : MySQL Release Engineering

Vendor : Oracle and/or its affiliates

URL : http://www.mysql.com/

Summary : A very fast and reliable SQL database server

出现以上信息说明安装成功

\5. 检查 mysql 源是否安装成功

yum repolist enabled | grep "mysql.*-community.*"

出现以下信息说明安装成功：

mysql-connectors-community MySQL Connectors Community 141

mysql-tools-community MySQL Tools Community 105

mysql57-community MySQL 5.7 Community Server

\6. 启动MySQL

systemctl start mysqld

复制代码

\7. 查看启动状态

systemctl status mysqld

出现以下信息，则启动成功

Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)

Active: active (running) since Sat 2020-02-22 11:14:47 CST; 2h 19min ago

Docs: man:mysqld(8)

http://dev.mysql.com/doc/refman/en/using-systemd.html

Process: 21345 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)

Process: 21323 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)

Main PID: 21349 (mysqld)

Tasks: 30 (limit: 11516)

Memory: 209.1M

CGroup: /system.slice/mysqld.service

?..21349 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid

\8. 设置开机启动

systemctl enable mysqld

\9. 刷新所有修改过的配置文件

systemctl daemon-reload

\10. 获取安装mysql后生成的临时密码，用于登录

grep 'temporary password' /var/log/mysqld.log

# 如果出现如下列信息，密码为: BL=azx(1u;Br

2020-02-22T03:05:17.741049Z 1 [Note] A temporary password is generated for root@localhost: BL=azx(1u;Br

\11. 登录MySQL

mysql -uroot -p

# 再输入上面查找得到的临时密码即可进入mysql

\12. 修改登录密码

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass4!(修改后的密码，注意必须包含大小写字母数字以及特殊字符并且长度不能少于8位,否则会报错)';

或者通过：mysql> set password for 'root'@'localhost'=password('MyNewPass4!');

或者通过：mysql> use mysql;

mysql> update user set password=PASSWORD('MyNewPass5!') where user='root';

mysql> flush privileges;

\13. 添加远程登录用户(即本机访问服务器上的MySQL)

mysql> GRANT ALL PRIVILEGES ON *.* TO 'zhangsan(用户名)'@'%' IDENTIFIED BY 'Zhangsan2018!(密码)' WITH GRANT OPTION;

# 或者直接将root权限修改为可以通过远程访问(但不推荐)

mysql> use mysql;

mysql> UPDATE user SET Host='%' WHERE User='root';

mysql> flush privileges;

\14. 设置默认编码为utf-8(mysql安装后默认不支持中文)

vim /etc/my.cnf

# 进入文件后添加下面的配置即可

[mysqld]

character-set-server=utf8

[client]

default-character-set=utf8

[mysql]

default-character-set=utf8

\15. 重启MySQL服务并进入MySQL

shell> systemctl restart mysqld

shell> mysql -uroot -p

mysql> show variables like 'character%';

出现如下则说明编码修改完成

+--------------------------+----------------------------+

| Variable_name | Value |

+--------------------------+----------------------------+

| character_set_client | utf8 |

| character_set_connection | utf8 |

| character_set_database | utf8 |

| character_set_filesystem | binary |

| character_set_results | utf8 |

| character_set_server | utf8 |

| character_set_system | utf8 |

| character_sets_dir | /usr/share/mysql/charsets/ |

+--------------------------+----------------------------+

退出MySQL

mysql> quit

使用本机电脑navicat/sqlyog等一系列客户端工具连接服务器上的mysql，用户名和密码为远程用户的用户名和密码，如果是将root权限修改为可以远程访问，就用root访问。