官網地址：https://dev.mysql.com/downloads/mysql/
我這里是RHEL6.5的系統，因此選擇RedHat 6 x86,64bit操作系統---下載第一個RPM Bundle即可--mysql-8.0.11-1.el6.x86_64.rpm-bundle.tar。
目前MySQL8.0.11社區版提供了多種多樣的安裝方式，你也可以通過下載Linux Generic安裝包mysql-8.0.11-linux-glibc2.12-x86_64.tar.gz來安裝，這種安裝方式無需考慮包兼容性，本文只描述rpm安裝方式。
wget https://cdn.mysql.com//Downloads/MySQL-8.0/mysql-8.0.11-1.el6.x86_64.rpm-bundle.tar
如果上述鏈接失效，一般是因為官網已經更新了新版本，找到最新版本的版本號修改下載即可。
一、mysql-8.0.11-1.el6.x86_64.rpm-bundle.tar解壓后有如下7個文件：
-rw-r--r-- 1 root root 28987588 Apr 9 01:06 mysql-community-client-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 672184 Apr 9 01:06 mysql-community-common-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 4443296 Apr 9 01:06 mysql-community-devel-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 2579460 Apr 9 01:06 mysql-community-libs-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 1902676 Apr 9 01:06 mysql-community-libs-compat-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 395918848 Apr 9 01:07 mysql-community-server-8.0.11-1.el6.x86_64.rpm -rw-r--r-- 1 root root 49092596 Apr 9 01:07 mysql-community-test-8.0.11-1.el6.x86_64.rpm
然后創建mysql用戶：
useradd mysql passwd mysql
二、安裝順序為：（強烈建議裝之前先把之前的或自帶的mysql相關包全部卸載，rpm -e --nodeps <包名>即可）
rpm -ivh mysql-community-common-8.0.11-1.el6.x86_64.rpm \ mysql-community-libs-8.0.11-1.el6.x86_64.rpm \ mysql-community-libs-compat-8.0.11-1.el6.x86_64.rpm \ mysql-community-client-8.0.11-1.el6.x86_64.rpm \ mysql-community-server-8.0.11-1.el6.x86_64.rpm \ mysql-community-devel-8.0.11-1.el6.x86_64.rpm
三、安裝完畢后相關信息如下：
[root@python ~]# mysql -V mysql Ver 8.0.11 for Linux on x86_64 (MySQL Community Server - GPL) [root@python ~]# ll /etc/init.d/mysqld -rwxr-xr-x 1 root root 7166 Apr 8 16:21 /etc/init.d/mysqld [root@python ~]# ll /etc/my.cnf --配置文件位置 -rw-r--r-- 1 root root 1188 Apr 8 16:21 /etc/my.cnf
默認的datadir是在/var/lib/mysql/，可以通過修改my.cnf修改，啟動命令如下：
[root@python ~]# service mysqld start Initializing MySQL database: [ OK ] Starting mysqld: [ OK ]
四、使用默認密碼登錄MySQL
在安裝完后，/var/log/mysqld.log里應該含有臨時的root密碼，可以直接登錄，你可以將此root密碼更改為自己更熟悉的密碼。
mysql> alter user root@'localhost' identified by 'mysql'; ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
這里存在密碼復雜度要求（在Windows平台使用msi安裝mysql時，則有自主選擇密碼認證方式的步驟，可以比較方便的進行設置。）：
mysql> show variables like '%pass%'; +----------------------------------------------+-----------------+ | Variable_name | Value | +----------------------------------------------+-----------------+ | caching_sha2_password_auto_generate_rsa_keys | ON | | caching_sha2_password_private_key_path | private_key.pem | | caching_sha2_password_public_key_path | public_key.pem | | default_password_lifetime | 0 | | disconnect_on_expired_password | ON | | mysql_native_password_proxy_users | OFF | | password_history | 0 | | password_reuse_interval | 0 | | report_password | | | sha256_password_auto_generate_rsa_keys | ON | | sha256_password_private_key_path | private_key.pem | | sha256_password_proxy_users | OFF | | sha256_password_public_key_path | public_key.pem | | validate_password.check_user_name | ON | | validate_password.dictionary_file | | | validate_password.length | 8 | | validate_password.mixed_case_count | 1 | | validate_password.number_count | 1 | | validate_password.policy | MEDIUM | | validate_password.special_char_count | 1 | +----------------------------------------------+-----------------+
發現此值有3個，如下所示：
於是設置為0，然后將validate_password.length設置為4，表示最少需要4字符。之所以設置為4是因為這個參數的值不能小於如下公式的計算結果：
validate_password.number_count + validate_password.special_char_count + (2 * validate_password.mixed_case_count)
五、建一個測試用戶leo，嘗試遠程連接下吧：
$ mysql -uleo -pmysql -h192.168.1.193 mysql: [Warning] Using a password on the command line interface can be insecure. ERROR 2059 (HY000): Authentication plugin 'caching_sha2_password' cannot be loaded: /usr/lib/mysql/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory
我這5.7的mysql工具都連不上，這就尷尬了，查看認證相關參數：
mysql> show variables like '%auth%'; +-------------------------------+-----------------------+ | Variable_name | Value | +-------------------------------+-----------------------+ | default_authentication_plugin | caching_sha2_password | +-------------------------------+-----------------------+ 1 row in set (0.02 sec)
查看官網發現此值的取值如下：
官網還說此值影響create user不顯式指定auth plugin時密碼的默認加密算法，這意味着低版本的mysql工具基本連不上8.0，簡單起見我們直接使用以前的加密算法。
mysql> select user,host,plugin from mysql.user; +------------------+-----------+-----------------------+ | user | host | plugin | +------------------+-----------+-----------------------+ | leo | % | caching_sha2_password | | mysql.infoschema | localhost | mysql_native_password | | mysql.session | localhost | mysql_native_password | | mysql.sys | localhost | mysql_native_password | | root | localhost | caching_sha2_password | +------------------+-----------+-----------------------+
在my.cnf里添加：default_authentication_plugin=mysql_native_password，然后service mysqld restart重啟服務，以下只演示leo用戶的創建：
mysql> drop user leo; Query OK, 0 rows affected (0.10 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec) mysql> create user leo identified by 'mysql'; Query OK, 0 rows affected (0.02 sec) mysql> grant all on *.* to leo; Query OK, 0 rows affected (0.08 sec)
$mysql -V mysql Ver 14.14 Distrib 5.7.20, for Linux (x86_64) using EditLine wrapper $ mysql -uleo -pmysql -h192.168.1.193 mysql: [Warning] Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 16 Server version: 8.0.11 MySQL Community Server - GPL Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved. 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>
至此遠程連接正常。