CentOS 7 执行 yum 更新时报错

当在 CentOS 7 系统中执行 yum update 命令时，可能会遇到以下错误信息：

Could not resolve host: mirrorlist.centos.org; Unknown error

Loaded plugins: fastestmirror, ovl
Loading mirror speeds from cached hostfile
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"

One of the configured repositories failed (Unknown),
and yum doesn't have enough cached data to continue. At this point the only
safe thing yum can do is fail. There are a few ways to work "fix" this:

    1. Contact the upstream for the repository and get them to fix the problem.

    2. Reconfigure the baseurl/etc. for the repository, to point to a working
       upstream. This is most often useful if you are using a newer
       distribution release than is supported by the repository (and the
       packages for the previous distribution release still work).

    3. Run the command with the repository temporarily disabled
           yum --disablerepo=<repoid> ...

    4. Disable the repository permanently, so yum won't use it by default. Yum
       will then just ignore the repository until you permanently enable it
       again or use --enablerepo for temporary usage:

           yum-config-manager --disable <repoid>
       or
           subscription-manager repos --disable=<repoid>

    5. Configure the failing repository to be skipped, if it is unavailable.
       Note that yum will try to contact the repo. when it runs most commands,
       so will have to try and fail each time (and thus. yum will be be much
       slower). If it is a very temporary problem though, this is often a nice
       compromise:

           yum-config-manager --save --setopt=<repoid>.skip_if_unavailable=true

Cannot find a valid baseurl for repo: base/7/x86_64

问题解决方案

自 2024 年 7 月 1 日起，CentOS 7 用户需要切换到 Vault 存档仓库以继续获取更新：

1. 打开 CentOS 基础配置文件：

vi /etc/yum.repos.d/CentOS-Base.repo

1. 清空文件内容，然后添加以下配置（注意根据您的系统版本进行相应调整，以下示例针对 7.9.2009 版本）：

[base]
name=CentOS-$releasever - Base
baseurl=http://vault.centos.org/7.9.2009/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

[updates]
name=CentOS-$releasever - Updates
baseurl=http://vault.centos.org/7.9.2009/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

[extras]
name=CentOS-$releasever - Extras
baseurl=http://vault.centos.org/7.9.2009/extras/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

[centosplus]
name=CentOS-$releasever - Plus
baseurl=http://vault.centos.org/7.9.2009/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

1. 清理 yum 缓存：

yum clean all

1. 执行系统更新：

yum update

通过以上步骤，您应该能够成功解决 CentOS 7 的 yum 更新问题。