2024年最新：配置CentOS 7阿里yum源
前言
根据 CentOS 官方公告，CentOS 7 已经于 2024 年 6 月 30 日结束支持，其软件仓库也相应被上游移除。
阿里云、TUNA等国内镜像站也都移除了各类软件为 CentOS 7（包括 el7, rhel7 或 centos7 等多种变体）提供的版本，因此网上很多设置CentOS 7 YUM源的教程已经不再适用。
不过阿里云、TUNA等国内镜像站也为CentOS 7等官方不再支持的版本提供了历史归档，还在使用CentOS 7的用户可以切换到对应的归档YUM源。
一、备份yum源配置文件
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo_bak
二、新建阿里云YUM源配置文件
下面将以CentOS 7.9为例配置阿里云yum源，其他版本的CentOS 7可以将配置文件中的7.9.2009全部替换为你使用的系统版本，如：7.8.2003、7.7.1908等
新建yum仓库配置文件
vi /etc/yum.repos.d/CentOS-Base.repo
点击i键进入编辑模式，将以下配置信息复制到配置文件中
# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client. You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the
# remarked out baseurl= line instead.
#
#
[base]
name=CentOS-$releasever - Base - mirrors.aliyun.com
failovermethod=priority
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/os/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-7
#released updates
[updates]
name=CentOS-$releasever - Updates - mirrors.aliyun.com
failovermethod=priority
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/updates/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-7
#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras - mirrors.aliyun.com
failovermethod=priority
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/extras/$basearch/
gpgcheck=1
gpgkey=https://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-7
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus - mirrors.aliyun.com
failovermethod=priority
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=https://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-7
#contrib - packages by Centos Users
[contrib]
name=CentOS-$releasever - Contrib - mirrors.aliyun.com
failovermethod=priority
baseurl=https://mirrors.aliyun.com/centos-vault/7.9.2009/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=https://mirrors.aliyun.com/centos-vault/RPM-GPG-KEY-CentOS-7
点击Esc键退出编辑模式，输入:wq保存配置文件
三、清除缓存并重建元数据缓存
yum clean all && yum makecache
至此阿里云YUM源已经切换成功，可以尽情使用了
