说明：
- 安装与卸载中，用户全部切换成为 root，一旦安装，普通用户就能使用。
一、卸载内置环境
1、卸载不要的环境
[root@VM-8-5-centos ~]$ ps ajx | grep mariadb # 先检查是否有mariadb存在 13134 14844 14843 13134 pts/0 14843 S+ 1005 0:00 grep --color=auto mariadb 19010 19187 19010 19010 ? -1 Sl 27 16:55 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --log- error=/var/log/mariadb/mariadb.log --pid-file=/var/run/mariadb/mariadb.pid -- socket=/var/lib/mysql/mysql.sock [root@VM-8-5-centos ~]$ systemctl stop mariadb.service # 停止mariadb服务 ==== AUTHENTICATING FOR org.freedesktop.systemd1.manage-units === Authentication is required to manage system services or units. Authenticating as: root Password: ==== AUTHENTICATION COMPLETE === [root@VM-8-5-centos ~]$ ps axj | grep mariadb # 停止完成 13134 14976 14975 13134 pts/0 14975 S+ 1005 0:00 grep --color=auto mariadb
mariadb 其实就是 mysql，只不过是 mysql 的另一种拉出来的开源分支，也可以正常使用，如果不想卸载也是可以的。
2、检查系统安装包
[root@VM-8-5-centos ~]$ rpm -qa | grep mariadb or [root@VM-8-5-centos ~]$ rpm -qa | grep mysql ... ... ... # 下面是打印出来的mysql的样例 [root@VM-8-5-centos ~]# rpm -qa | grep mysql mysql-community-common-5.7.41-1.el7.x86_64 mysql-community-server-5.7.41-1.el7.x86_64 mysql57-community-release-el7-11.noarch mysql-community-client-5.7.41-1.el7.x86_64 mysql-community-libs-5.7.41-1.el7.x86_64
3、卸载这些默认的安装包
#卸载显示出来的mariadb/mysql安装包 [root@VM-8-5-centos ~]$ sudo yum remove mariadb # 还是试着将上面的包都一个一个卸载吧 备份/etc/my.cnf,备份/var/lib/mysql数据
4、获取 mysql 官方 yum 源
下载 MySQL yum包：
wget http://repo.mysql.com/mysql57-community-release-el7-10.noarch.rpm
#1. 获取mysql官方yum源 http://repo.mysql.com/ # 一定要看好下面的文字！如果后面自己安装不成功，就看看这个 # 注意：最好安装和自己系统一致的mysql版本，否则可能会存在软件兼容性问题 # 查看自己的系统版本 # [root@VM-8-5-centos ~]# cat /etc/redhat-release # CentOS Linux release 7.8.2003(Core) # 可以进入 http://repo.mysql.com/，找一下和自己版本一致的资源 # 下载到你的本地，然后上传到你的Linux服务器
二、 配置 MySQL yum 源
1、安装 mysql yum 源，对比前后 yum 源
安装 MySQL 源：rpm -Uvh mysql57-community-release-el7-10.noarch.rpm
安装前 [root@VM-8-5-centos MySQL]$ ls mysql57-community-release-el7-10.noarch.rpm 查看你本地的yum源 [每个人的都不同，没有mysql相关的yum源] [root@VM-8-5-centos MySQL]$ ls /etc/yum.repos.d/ -al total 96 drwxr-xr-x. 2 root root 4096 Apr 12 11:04 . drwxr-xr-x. 106 root root 12288 Apr 12 10:50 .. -rw-r--r-- 1 root root 2523 Dec 26 19:31 Centos-Base.repo -rw-r--r-- 1 root root 614 Nov 10 18:42 CentOS-Base.repo_bak -rw-r--r-- 1 root root 2523 Jun 16 2018 CentOS-Base.repo.bak -rw-r--r-- 1 root root 1309 Apr 8 2020 CentOS-CR.repo -rw-r--r-- 1 root root 649 Apr 8 2020 CentOS-Debuginfo.repo -rw-r--r-- 1 root root 230 Nov 10 18:42 CentOS-Epel.repo -rw-r--r-- 1 root root 314 Apr 8 2020 CentOS-fasttrack.repo -rw-r--r-- 1 root root 630 Apr 8 2020 CentOS-Media.repo -rw-r--r-- 1 root root 998 Dec 11 2018 CentOS-SCLo-scl.repo -rw-r--r-- 1 root root 971 Oct 29 2018 CentOS-SCLo-scl-rh.repo -rw-r--r-- 1 root root 1331 Apr 8 2020 CentOS-Sources.repo -rw-r--r-- 1 root root 7577 Apr 8 2020 CentOS-Vault.repo -rw-r--r-- 1 root root 616 Apr 8 2020 CentOS-x86_64-kernel.repo -rw-r--r-- 1 root root 1919 Apr 8 23:57 docker-ce.repo -rw-r--r-- 1 root root 1050 Nov 1 04:33 epel.repo -rw-r--r-- 1 root root 1149 Nov 1 04:33 epel-testing.repo -rw-r--r-- 1 root root 173 Dec 9 16:08 google-chrome.repo -rw-r--r-- 1 root root 1627 Apr 5 2017 mysql-community.repo #安装mysql yum源 -rw-r--r-- 1 root root 1663 Apr 5 2017 mysql-community-source.repo
2、再看看能不能正常工作
[root@VM-8-5-centos MySQL]$ yum list |grep mysql Repository epel is listed more than once in the configuration mysql57-community-release.noarch el7-10 installed akonadi-mysql.x86_64 1.9.2-4.el7 base anope-mysql.x86_64 2.0.9-3.el7 epel apr-util-mysql.x86_64 1.5.2-6.el7 base calligra-kexi-driver-mysql.x86_64 2.9.10-2.el7 epel collectd-mysql.x86_64 5.8.1-1.el7 epel dmlite-plugins-mysql.x86_64 1.14.2-1.el7 epel dovecot-mysql.x86_64 1:2.2.36-8.el7 base
一开始的时候我们安装的 yum，在安装完之后是可以选择删除的，因为每次 yum 操作都会更新一次，耗费时间。
rpm -qa | grep mysql
yum -y remove mysql57-community-release-el7-10.noarch
三、开始安装
1、安装 mysql 服务
安装 MySQL 服务端，需要等待一些时间：yum install -y mysql-community-server
[root@VM-8-5-centos MySQL]$ sudo yum install -y mysql-community-server [sudo] password for root: Loaded plugins: aliases, auto-update-debuginfo, fastestmirror, protectbase Repository epel is listed more than once in the configuration ... Installing : mysql-community-common-5.7.33-1.el7.x86_64 #公共模块 Installing : mysql-community-libs-5.7.33-1.el7.x86_64 #库 Installing : mysql-community-client-5.7.33-1.el7.x86_64 #客户端 Installing : mysql-community-server-5.7.33-1.el7.x86_64 #服务器 ... #安装了服务和客户端 # 如果报错了，看第16步《常见问题》
2、查看配置文件和数据存储位置
[root@VM-8-5-centos MySQL]$ ls /etc/my.cnf /etc/my.cnf [root@VM-8-5-centos MySQL]$ sudo ls /var/lib/mysql ....
3、启动服务
启动 MySQL：systemctl start mysqld.service
[root@VM-8-5-centos MySQL]$ systemctl start mysqld.service ==== AUTHENTICATING FOR org.freedesktop.systemd1.manage-units === Authentication is required to manage system services or units. Authenticating as: root Password: ==== AUTHENTICATION COMPLETE ===
4、查看启动服务
检查是否启动成功：systemctl status mysqld.service
[root@VM-8-5-centos MySQL]$ ps axj |grep mysqld 1 23183 23182 23182 ? -1 Sl 27 0:00 /usr/sbin/mysqld --daemonize -- pid-file=/var/run/mysqld/mysqld.pid 13134 23243 23242 13134 pts/0 23242 S+ 1005 0:00 grep --color=auto mysqld [root@VM-8-5-centos MySQL]$ sudo ls -al /var/lib/mysql total 122956 drwxr-x--x 5 mysql mysql 4096 Apr 12 11:23 . drwxr-xr-x. 39 root root 4096 Apr 12 11:11 .. -rw-r----- 1 mysql mysql 56 Apr 12 11:23 auto.cnf -rw------- 1 mysql mysql 1680 Apr 12 11:23 ca-key.pem -rw-r--r-- 1 mysql mysql 1112 Apr 12 11:23 ca.pem -rw-r--r-- 1 mysql mysql 1112 Apr 12 11:23 client-cert.pem -rw------- 1 mysql mysql 1676 Apr 12 11:23 client-key.pem -rw-r----- 1 mysql mysql 436 Apr 12 11:23 ib_buffer_pool -rw-r----- 1 mysql mysql 12582912 Apr 12 11:23 ibdata1 -rw-r----- 1 mysql mysql 50331648 Apr 12 11:23 ib_logfile0 -rw-r----- 1 mysql mysql 50331648 Apr 12 11:23 ib_logfile1 -rw-r----- 1 mysql mysql 12582912 Apr 12 11:23 ibtmp1 drwxr-x--- 2 mysql mysql 4096 Apr 12 11:23 mysql srwxrwxrwx 1 mysql mysql 0 Apr 12 11:23 mysql.sock -rw------- 1 mysql mysql 6 Apr 12 11:23 mysql.sock.lock drwxr-x--- 2 mysql mysql 4096 Apr 12 11:23 performance_schema -rw------- 1 mysql mysql 1680 Apr 12 11:23 private_key.pem -rw-r--r-- 1 mysql mysql 452 Apr 12 11:23 public_key.pem -rw-r--r-- 1 mysql mysql 1112 Apr 12 11:23 server-cert.pem -rw------- 1 mysql mysql 1680 Apr 12 11:23 server-key.pem drwxr-x--- 2 mysql mysql 12288 Apr 12 11:23 sys
四、开始登陆
1、登陆方法一【不行就下一个】
获取临时密码，MySQL5.7 为 root 用户随机生成了一个密码：
grep 'temporary password' /var/log/mysqld.log
#获取临时root密码 [root@VM-8-5-centos MySQL]$ sudo grep 'temporary password' /var/log/mysqld.log 2021-04-12T03:23:46.153263Z 1 [Note] A temporary password is generated for root@localhost: yLMalT:v+5l* #使用临时密码登录 [root@VM-8-5-centos MySQL]$ mysql -uroot -p Enter password: #判断修改密码时候新密码是否符合当前的策略，不满足报错，不让修改，关闭它 #安全强度，默认为中，即1，要求必须包含 数字、符号、大小写字母，长度至少为8位 mysql> set global validate_password_policy=0; Query OK, 0 rows affected (0.00 sec) #密码最小长度 mysql> set global validate_password_length=1; Query OK, 0 rows affected (0.00 sec) #修改本地登录密码，暂不授权远程登录 mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'yourpassword'; Query OK, 0 rows affected (0.00 sec) mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.00 sec) # 如果你安装最新的mysql，没有所谓的临时密码，root默认没有密码
通过临时密码登录 MySQL，进行修改密码操作：mysql -uroot -p
使用临时密码登录后，不能进行其他的操作，否则会报错，这时候我们进行修改密码操作。
因为 MySQL 的密码规则需要很复杂，我们一般自己设置的不会设置成这样，所以我们全局修改一下：
mysql> set global validate_password_policy=0;
mysql> set global validate_password_length=1;
这时候我们就可以自己设置想要的密码了。
ALTER USER 'root'@'localhost' IDENTIFIED BY 'yourpassword';
2、登陆方法二【不行就下一个】
# 如果你安装的最新的mysql，没有所谓的临时密码，root默认没有密码 # 试着直接client登陆一下
3、登陆方法三【应该行了吧】
[root@VM-8-5-centos MySQL]# vim /etc/my.cnf # 打开mysql配置文件 在[mysqld]最后一栏配置(不知道是什么，就放在配置文件最后) 加入：skip-grant-tables 选项，并保存退出 [root@VM-8-5-centos MySQL]# systemctl restart mysqld # 重启mysql服务 # 登陆成功 [root@VM-8-5-centos MySQL]# mysql -uroot Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 7 Server version: 5.7.44 MySQL Community Server (GPL) Copyright (c) 2000, 2023, Oracle and/or its affiliates. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql>
五、设置配置文件
1、设置开机启动【可以不设】
先退出 mysql 命令行，然后输入以下命令：
#开启开机自启动 systemctl enable mysqld systemctl daemon-reload
2、配置 my.cnf
设置 MySQL 的字符集为 UTF-8，令其支持中文：
vim /etc/my.cnf
#配置一下my.conf,主要是数据库客户端和服务器的编码格式 [root@VM-8-5-centos MySQL]$ cat /etc/my.cnf # For advice on how to change settings please see # http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html [mysqld] # # Remove leading # and set to the amount of RAM for the most important data # cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%. # innodb_buffer_pool_size = 128M # # Remove leading # to turn on a very important data integrity option: logging # changes to the binary log between backups. # log_bin # # Remove leading # to set options mainly useful for reporting servers. # The server defaults are faster for transactions and fast SELECTs. # Adjust sizes as needed, experiment to find the optimal values. # join_buffer_size = 128M # sort_buffer_size = 2M # read_rnd_buffer_size = 2M port=3306 character-set-server=utf8 default-storage-engine=innodb datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 character-set-server=utf8 default-storage-engine=innodb log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid skip-grant-tables # 配置完毕，重启mysql即可
重启一下 MySQL，令配置生效：
重启 mysql：service mysqld restart
or
停止 mysql：service mysqld stop
启动 mysql：service mysqld start
3、常见问题：
mysql 已经配置了客户端服务器utf8编码，但是无法输入中文 确保您在终端命令行中可以输入中文 [root@VM-8-5-centos ~]$ env | grep LANG LANG=en_US.utf8
安装遇到秘钥过期的问题： Failing package is: mysql-community-client-5.7.39-1.EL7.86_64 GPG Keys are configured as: file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql 解决方案: rpm --import https://repo.mysql.com/RPM-GPG-KEY-mysql-2022
