Linux CentOS stream9配置本地yum源
在Linux系统中，yum源配置是一个重要的环节。把系统安装时配置的国外yum源转换为国内yum源，能够帮助系统快速安装软件包。对于网络环境不稳定或无法联网的系统，配置本地yum源，可以让用户在离线状态下也能进行软件包的安装，十分重要。
一、国内源
在使用Linux的日常工作中，经常会遇到缺少包的情况，而当我们单独下载缺少的包进行安装时，大多都会因为依赖或版本与操作系统版本不兼容的问题，这个时候配置yum就显得很有必要
配置yum源一般分两种情况，网络yum源和本地iyum源。
1.网络yum源
网络yum源通常在能连接互联网的服务器上进行配置，配置简单，可选择性强，能获取的包也更多；用国内yum源替换系统自带的yum源，对于本版本的设置，可参考《Linux CentOS7 yum仓库》。
主要配置文件：
a. centos.repo
[baseos]
name=CentOS Stream $releasever - BaseOS
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/BaseOS/$basearch/os
# metalink=https://mirrors.centos.org/metalink?repo=centos-baseos-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
countme=1
enabled=1
[baseos-debuginfo]
name=CentOS Stream $releasever - BaseOS - Debug
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/BaseOS/$basearch/debug/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-baseos-debug-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
enabled=0
[baseos-source]
name=CentOS Stream $releasever - BaseOS - Source
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/BaseOS/source/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-baseos-source-$stream&arch=source&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
enabled=0
[appstream]
name=CentOS Stream $releasever - AppStream
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/AppStream/$basearch/os
# metalink=https://mirrors.centos.org/metalink?repo=centos-appstream-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
countme=1
enabled=1
[appstream-debuginfo]
name=CentOS Stream $releasever - AppStream - Debug
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/AppStream/$basearch/debug/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-appstream-debug-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
enabled=0
[appstream-source]
name=CentOS Stream $releasever - AppStream - Source
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/AppStream/source/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-appstream-source-$stream&arch=source&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
enabled=0
[crb]
name=CentOS Stream $releasever - CRB
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/CRB/$basearch/os
# metalink=https://mirrors.centos.org/metalink?repo=centos-crb-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
countme=1
enabled=1
[crb-debuginfo]
name=CentOS Stream $releasever - CRB - Debug
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/CRB/$basearch/debug/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-crb-debug-$stream&arch=$basearch&protocol=https,http
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial
gpgcheck=1
repo_gpgcheck=0
metadata_expire=6h
enabled=0
[crb-source]
name=CentOS Stream $releasever - CRB - Source
baseurl=https://mirrors.tuna.tsinghua.edu.cn/centos-stream/$releasever-stream/CRB/source/tree/
# metalink=https://mirrors.centos.org/metalink?repo=centos-crb-source-$stream&arch=