diff --git a/help/_posts/1970-01-01-centos.md b/help/_posts/1970-01-01-centos.md
index 57c997b..cd88893 100644
--- a/help/_posts/1970-01-01-centos.md
+++ b/help/_posts/1970-01-01-centos.md
@@ -6,134 +6,24 @@ mirrorid: centos
 
 ## CentOS 镜像使用帮助
 
-建议先备份 CentOS-Base.repo
+该文件夹只提供 CentOS 7 与 8，架构仅为 `x86_64` ，如果需要较早版本的 CentOS，请参考 centos-vault 的帮助，若需要其他架构，请参考 centos-altarch 的帮助。
+
+建议先备份 `/etc/yum.repos.d/` 内的文件（CentOS 7 及之前为 `CentOS-Base.repo`，CentOS 8 为`CentOS-Linux-*.repo`）
+
+然后编辑 `/etc/yum.repos.d/` 中的相应文件，在 `mirrorlist=` 开头行前面加 `#` 注释掉；并将 `baseurl=` 开头行取消注释（如果被注释的话），把该行内的域名（例如`mirror.centos.org`）替换为 `{{ site.hostname }}`。
+
+以上步骤可以被下方的命令一步完成
 
 ```
-sudo cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
+sudo sed -e 's|^mirrorlist=|#mirrorlist=|g' \
+         -e 's|^#baseurl=http://mirror.centos.org|baseurl=https://{{ site.hostname }}|g' \
+         -i.bak \
+         /etc/yum.repos.d/CentOS-*.repo
 ```
 
-然后编辑 /etc/yum.repos.d/CentOS-Base.repo 文件，在 `mirrorlist=` 开头行前面加 `#` 注释掉；并将 `baseurl=` 开头行取消注释（如果被注释的话），把该行内的域名（例如`mirror.centos.org`）替换为 `{{ site.hostname }}`。
+注意其中的`*`通配符，如果只需要替换一些文件中的源，请自行增删。
 
-或者，你也可以直接使用如下内容覆盖掉 /etc/yum.repos.d/CentOS-Base.repo 文件：（未经充分测试）
-
-<form class="form-inline">
-<div class="form-group">
-	<label>选择你的 CentOS 版本: </label>
-	<select class="form-control release-select" data-template="#repo-template" data-target="#repo-content">
-	  <option data-os="" data-security="RPM-GPG-KEY-5" data-release="5">CentOS 5</option>
-	  <option data-os="" data-security="RPM-GPG-KEY-6" data-release="6">CentOS 6</option>
-	  <option data-os="" data-security="RPM-GPG-KEY-7" data-release="7" selected>CentOS 7</option>
-	  <option data-os="os/" data-security="RPM-GPG-KEY-centosofficial" data-release="8">CentOS 8</option>
-	</select>
-</div>
-</form>
-
-{% raw %}
-<script id="repo-template" type="x-tmpl-markup">
-# 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.
-#
-#
-
-{{if release_name|between>5>7}}
-[base]
-name=CentOS-$releasever - Base
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/os/$basearch/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-
-#released updates
-[updates]
-name=CentOS-$releasever - Updates
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/updates/$basearch/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-{{/if}}
-{{if release_name|equals>8}}
-[BaseOS]
-name=CentOS-$releasever - Base
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/BaseOS/$basearch/os/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=BaseOS&infra=$infra
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-
-[AppStream]
-name=CentOS-$releasever - AppStream
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/AppStream/$basearch/os/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=AppStream&infra=$infra
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-
-[PowerTools]
-name=CentOS-$releasever - PowerTools
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/PowerTools/$basearch/os/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=PowerTools&infra=$infra
-enabled=0
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-{{/if}}
-
-#additional packages that may be useful
-[extras]
-name=CentOS-$releasever - Extras
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/extras/$basearch/{{os_name}}
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-
-{{if release_name|equals>5}}
-#packages used/produced in the build but not released
-[addons]
-name=CentOS-$releasever - Addons
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/addons/$basearch/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=addons
-enabled=1
-gpgcheck=1
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-{{/if}}
-
-#additional packages that extend functionality of existing packages
-[centosplus]
-name=CentOS-$releasever - Plus
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/centosplus/$basearch/{{os_name}}
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus
-gpgcheck=1
-enabled=0
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-
-{{if release_name|between>5>6}}
-#contrib - packages by Centos Users
-[contrib]
-name=CentOS-$releasever - Contrib
-baseurl=https://{%endraw%}{{ site.hostname }}{%raw%}/centos/$releasever/contrib/$basearch/
-#mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=contrib
-gpgcheck=1
-enabled=0
-gpgkey=file:///etc/pki/rpm-gpg/{{release_security}}
-{{/if}}
-</script>
-{% endraw %}
-
-<p></p>
-
-<pre>
-<code id="repo-content">
-</code>
-</pre>
+注意，如果需要启用其中一些 repo，需要将其中的 `enabled=0` 改为 `enabled=1`。
 
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