重新换vps，用centos8，重新配置系统环境，记下笔记：

安装nginx与php

首先安装nginx php ,安装默认版本的nginx，php默认安装7 

yum install nginx php  

系统罗列安装详细信息，输入yes即可

nginx状态设置

启动nginx

systemctl start nginx.service

查看nginx状态

systemctl status nginx

设置开机启动

 systemctl enable nginx.service

显示 enbaled 则设置开机启动成功

systemctl is-enabled nginx.service;echo $? 

php状态设置

启动php

systemctl start php-fpm

查看php 当前版本

php -v

设置php开机启动

systemctl enable php-fpm

 如果要运行phpcms 还要安装gd json mysql库

 yum install  php-gd php-msyql php-json

如果不知道名字，yum search  php ，查看相关扩张库

安装以下扩张库 

yum -y install php-json php-xml  php-mysqlnd php-mbstring  php-common  php-gd 

##  yum -y install php72w-cli php72w-common php7php2w-devel php72w-embedded php72w-fpm php72w-gd php72w-mbstring php72w-mysqlnd php72w-opcache php72w-pdo php72w-xml

如果需要安装php5.6

rpm -Uvh https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm

yum install php56w php56w-opcache  php56w-fpm

查看php版本

php -V

mysql安装

centos 默认安装的mysql8.0，我希望安装5.6，需要收手工安装。

首先参考下网上的方法：

centos7 安装mysql5.6 https://www.cnblogs.com/lulin9501/p/11069093.html

需要编译，放弃，推荐，参考此篇方法，安装。精炼如下：

按照此篇方法 安装，CentOS 7系统安装nginx+php+mysql https://blog.csdn.net/YZJ0517/article/details/85542304

启动mysql，报 Failed to start mysqld.service: Unit mysqld.service not found. 错误

推荐： CentOS7下使用YUM安装MySQL5.6 https://blog.csdn.net/pengjunlee/article/details/81212250

查看是否安装MySQL

rpm -qa | grep mysql

下载安装包文件

wget http://repo.mysql.com/mysql-community-release-el7-5.noarch.rpm

安装mysql-community-release-el7-5.noarch.rpm包

rpm -ivh mysql-community-release-el7-5.noarch.rpm

查看可用安装包

yum repolist all | grep mysql

安装mysql

yum install mysql-server

检查mysql是否安装成功。

rpm -qa | grep mysql

启动 mysql 服务 

systemctl start mysqld.service

设置密码

mysql -u root
mysql> use mysql;
mysql> update user set password=PASSWORD("这里输入root用户密码") where User='root';
mysql> flush privileges;

设置mysql字符集

character_set_server = utf8

default-character-set = utf8

或者 vim /etc/my.cnf

设置为 ：

character_set_server=utf8
init_connect='SET NAMES utf8'

参考文章：

How to Install Apache/PHP 7 on CentOS/RHEL 7.5/6.9 and Fedora 28-26 https://tecadmin.net/install-apache-php-on-centos-fedora/

CentOS7下使用YUM安装MySQL5.6 https://blog.csdn.net/pengjunlee/article/details/81212250

centos7 安装mysql5.6 https://www.cnblogs.com/lulin9501/p/11069093.html

Failed to start mysqld.service: Unit not found  https://blog.csdn.net/miaodichiyou/article/details/99289160 

总结：

安装mysql 推荐：CentOS 7系统安装nginx+php+mysql https://blog.csdn.net/YZJ0517/article/details/85542304