1.先查询是否安装MySQL
大多数centos 6 自带 MySQL5.1
命令：
rpm -qa|grep mysql执行：
[root@lifan ~]# rpm -qa|grep mysql mysql-libs-5.1.73-7.el6.i6862.若有则卸载
rpm -e --nodeps mysql-libs--nodeps 是消除依赖的意思
3.去官网复制yum下载链接用wget下载到服务器
https://dev.mysql.com/downloads/repo/yum/命令：
wget https://dev.mysql.com/get/mysql80-community-release-el6-1.noarch.rpm成功：
[root@lifan ~]# wget https://dev.mysql.com/get/mysql80-community-release-el6-1.noarch.rpm --2018-12-10 06:40:42-- ... Length: 25800 (25K) [application/x-redhat-package-manager] Saving to: “mysql80-community-release-el6-1.noarch.rpm” 2018-12-10 06:40:42 (95.8 MB/s) - “mysql80-community-release-el6-1.noarch.rpm” saved [25800/25800]若没有wget
[root@lifan ~]# wget https://dev.mysql.com/get/mysql80-community-release-el6-1.noarch.rpm -bash: wget: command not found安装wget
yum -y install wget4.安装
第一步：
yum install https://repo.mysql.com//mysql80-community-release-el6-3.noarch.rpm
rpm -ivh mysql80-community-release-el6-1.noarch.rpm执行成功结果：
[root@lifan ~]# rpm -ivh mysql80-community-release-el6-1.noarch.rpm warning: mysql80-community-release-el6-1.noarch.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY Preparing... ########################################### [100%] 1:mysql80-community-relea########################################### [100%] [root@lifan ~]#第二步：
yum install mysql-server执行后会跳出2次选择，输入y回车继续即可，如：
[root@lifan ~]# yum install mysql-server Loaded plugins: fastestmirror ... Install 5 Package(s) Total download size: 452 M Installed size: 1.7 G Is this ok [y/N]: y输入y继续安装：
... Total 16 MB/s | 452 MB 00:28 warning: rpmts_HdrFromFdno: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql Importing GPG key 0x5072E1F5: Userid : MySQL Release Engineering <mysql-build@oss.oracle.com> Package: mysql80-community-release-el6-1.noarch (installed) From : /etc/pki/rpm-gpg/RPM-GPG-KEY-mysql Is this ok [y/N]: y最后出现如下指令，安装成功：
Installed: mysql-community-server.i686 0:8.0.13-1.el6 Dependency Installed: mysql-community-client.i686 0:8.0.13-1.el6 mysql-community-common.i686 0:8.0.13-1.el6 mysql-community-libs.i686 0:8.0.13-1.el6 numactl.i686 0:2.0.9-2.el6 Complete!5.查询是否安装成功
[root@lifan ~]# mysqladmin -V mysqladmin Ver 8.0.13 for Linux on i686 (MySQL Community Server - GPL)6.开启MySqL
[root@lifan ~]# service mysqld start Initializing MySQL database: [ OK ] Starting mysqld: [ OK ]查看MySQL启动状态:
[root@lifan ~]# service mysqld status mysqld (pid 3852) is running...7.查看系统给root自动生成的密码
cat /var/log/mysqld.log执行结果（密码在第二行最后）：
[root@lifan ~]# cat /var/log/mysqld.log 2018-12-10T12:19:20.303739Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.13) initializing of server in progress as process 3620 2018-12-10T12:19:24.878215Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: >J9tXQXwK3y= 2018-12-10T12:19:29.237165Z 0 [System] [MY-013170] [Server] /usr/sbin/mysqld (mysqld 8.0.13) initializing of server has completed 2018-12-10T12:19:32.011310Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.13) starting as process 3852 2018-12-10T12:19:33.144590Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed. 2018-12-10T12:19:33.201007Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: '8.0.13' socket: '/var/lib/mysql/mysql.sock' port: 3306 MySQL Community Server - GPL. 2018-12-10T12:19:33.272837Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: '/var/run/mysqld/mysqlx.sock' bind-address: '::' port: 330608.命令行登录和修改密码
[root@lifan ~]# mysql -uroot -p Enter password:输入上一步骤查看的密码（输入时不显示任何字符）：
[root@lifan ~]# mysql -uroot -p Enter password: Welcome to the MySQL monitor. ... mysql>修改密码：
mySql5.7之后，必须修改密码后才能操作. 并且对密码要求严格，至少8位，包含大小写等，若想设置成123456，则要以下两条命令： mysql> set global validate_password.policy=0; Query OK, 0 rows affected (0.00 sec) mysql> set global validate_password.length=1; Query OK, 0 rows affected (0.00 sec)设置密码：
mysql> alter user user() identified by '123456'; Query OK, 0 rows affected (0.09 sec)9.远程登录（Navicat）
注意：需关闭防火墙或者开放3306端口
service iptables stop #暂时关闭 chkconfig iptables off #设置成开启不自启 ========== /sbin/iptables -I INPUT -p tcp --dport 3306 -j ACCEPT #开启3306端口 /etc/rc.d/init.d/iptables save #保存配置 /etc/rc.d/init.d/iptables restart #重启服务远程登录会报如下错误：
首先查看用户表，发现登录主机是localhost，当然不能登录，把root用户的localhost设置为%，这样任意主机都可以连接。
mysql> use mysql; Database changed mysql> select user,host from user; +------------------+-----------+ | user | host | +------------------+-----------+ | mysql.infoschema | localhost | | mysql.session | localhost | | mysql.sys | localhost | | root | localhost | +------------------+-----------+ 4 rows in set (0.00 sec) mysql> update user set host = '%' where user ='root';再刷新一下:
flush privileges;这时该问题已解决，若报如下错误，则是版本加密方式的改变
登录后请依次执行如下命令：
use mysql; ALTER USER 'root'@'%' IDENTIFIED BY '123456' PASSWORD EXPIRE NEVER; #更改加密方式 ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';#更新用户密码 FLUSH PRIVILEGES;#刷新权限再次连接成功：
