centOS7使用yum安装报错的解决办法

一、错误提示信息：

[root@localhost /]# sudo yum install bash-completion
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock error was
14: curl#7 - "Failed to connect to 2a05:d012:8b5:6503:9efb:5cad:348f:e826: 网络不可达"

 One of the configured repositories failed (未知),
 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= ...

     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
        or
            subscription-manager repos --disable=

     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=.skip_if_unavailable=true

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

2解决办法：

感谢博主菜鸟小杰子提供的多种方法。我采用了第二种方法

《CentOS 7 镜像源失效终极解决方案（2024年更新）》——生命周期终止后的镜像修复与替代方案_centos7 镜像仓库都失效了-CSDN博客

二、使用第三方镜像源（推荐）

国内主流云厂商（如阿里云、腾讯云）仍维护CentOS 7的镜像仓库，更新更及时且访问稳定。

以阿里云镜像为例。

# 进入仓库配置目录（我是直接删除了repos.d内的文件，没有备份，请大家还是要备份的）
cd /etc/yum.repos.d/
 
# 备份原有配置
sudo mkdir backup && sudo mv CentOS-* backup/
 
# 下载阿里云镜像配置
sudo curl -O http://mirrors.aliyun.com/repo/Centos-7.repo
 
# 重建缓存
sudo yum clean all && sudo yum makecache

 三、问题得以解决