(A) Overview
RPM（Redhat Pagckage Manage）
Installation rpm coated with yum manner, with pip installation package python
Packages Category:
Common binary packages:
View yum install Source: yum repolist
(B) to the underlying source
After installing centos, there will be three default source (usually after installing centos The first thing is to update the system software, use the "yum update" to update the command from the base updates extras in), Base / Extras / Updates, as follows:
The source configuration file /etc/yum.repos.d/CentOS-Base.repo in to view this file can be found in the configuration of base updates extras centosplus (this because the configuration of the enabled = 0 it is not turned on by default, so no yum repolist found)
(3) The modification installation source
Since the default yum source of foreign links, it can lead to problems installing the software update is slow, so we can modify the installation source for some of the country's default installation source abroad.
1. modify aliyun / 163
1-1) into the search mirrors.aliyun.com https://developer.aliyun.com/mirror/centos?spm=a2c6h.13651102.0.0.3e221b11yCqugo
Like steps in accordance with the operation of the page, the following is a modified example of the operation:
2. EPEL source ( Extra Packages Standard Package for Enterprise Linux (EPEL) ) Linux Enterprise Edition installation package extra
Since the base extras updates only to provide some software systems related, some not found in the three source software, so
EPEL源地址： https://fedoraproject.org/wiki/EPEL
怎么安装EPEL源呢？直接使用命令： yum -y install epel-release
安装完成epel后，在epel中就可以找到nginx：
3. 把epel源也修改为国内源
同样，阿里云也提供了epel的源：https://developer.aliyun.com/mirror/epel?spm=a2c6h.13651102.0.0.3e221b11yCqugo
按照页面操作执行就可以了。
配置完成后，查看 vim /etc/yum.repos.d/epel.repo 里面都是aliyun的地址了。
