1，配置CentOs8的yum源
vim /etc/yum.repos.d/CentOS-AppStream.repo
[AppStream]
name=CentOS-$releasever - AppStream
baseurl=http://mirrors.aliyun.com/centos/$releasever/AppStream/$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
vim /etc/yum.repos.d/CentOS-Base.repo
[BaseOS]
name=CentOS-$releasever - Base
baseurl=http://mirrors.aliyun.com/centos/$releasever/BaseOS/$basearch/os/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
vim /etc/yum.repos.d/CentOS-Epel.repo
[epel]
name=CentOS-$releasever - Epel
baseurl=http://mirrors.aliyun.com/epel/8/Everything/$basearch
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-8
2，yum源配置成功后
yum clean all #命令清除yum緩存元數據
3，yum makecache #重新建立yum緩存
4，安裝epel存儲庫
sudo dnf -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
5，確認epel庫是否安裝成功
rpm -qa | grep epel
6，安裝remi存儲庫
dnf install https://rpms.remirepo.net/enterprise/remi-release-8.rpm
7，確認remi存儲庫是否安裝成功
8，成功添加EPEL和Remi存儲庫后，執行以下命令以獲取可用PHP模塊流的列表
dnf module list php
9，dnf module reset php #重置php模塊
10，根據第八步中的php流模塊，啟用對應php版本的流模塊，這里我們安裝的是php7.4的版本，所以啟用remi-7.4版本的流
dnf module enable php:remi-7.4
11，安裝PHP，此命令還安裝許多其他軟件包
dnf install php php-cli php-common
12，查看php是否安裝成功
