Centos8安装MySQL5.7

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

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

3. 下载完成后检查版本 (出现以下信息说明安装成功 )

[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

4. 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

5.. 启动MySQL

systemctl start mysqld

6. 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

7. 设置开机启动

systemctl enable mysqld

8. 刷新所有修改过的配置文件

systemctl daemon-reload

9. 获取安装mysql后生成的临时密码，用于登录

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

出现如下面信息，密码为: azx(1u;Br

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

10. 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

11. 修改登录密码

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '新密码（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('新密码');
或者通过：mysql> use mysql;
        mysql> update user set password=PASSWORD('新密码') where user='root';
        mysql> flush privileges;

12. 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 '用户名'@'%' IDENTIFIED BY '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;

13. 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

14. 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/ | 
+--------------------------+----------------------------+ 

15. 退出MySQL

mysql> quit