CentOS 7 的官方仓库在 2024 年 6 月 30 日之后已经停止维护。因此，使用最新的 CentOS 7 官方仓库可能会遇到问题。
解决failure: repodata/repomd.xml from centos: [Errno 256] No more mirrors to try.
http://mirrors.aliyun.com/centos/7/x86_64/os/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
1.到yum.repos.d目录
只需要保留一个文件即可，CentOS-Base.repo，其余文件可以全部删除。
cd /etc/yum.repos.d #删除该目录下所有文件 rm -rf *
2./etc/yum.repos.d目录下新增CentOS-Base.repo
新增文件：CentOS-Base.repo
vi CentOS-Base.repo,然后复制以下文本，粘贴。
# 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-$releasever - Base #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra #baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/ #baseurl=http://vault.centos.org/7.8.2003/x86_64/os/ baseurl=http://vault.centos.org/7.8.2003/os/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7 #released updates [updates] name=CentOS-$releasever - Updates #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra #baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/ #baseurl=http://vault.centos.org/7.8.2003/x86_64/os/ baseurl=http://vault.centos.org/7.8.2003/updates/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7 #additional packages that may be useful [extras] name=CentOS-$releasever - Extras #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras&infra=$infra #$baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/ #baseurl=http://vault.centos.org/7.8.2003/x86_64/os/ baseurl=http://vault.centos.org/7.8.2003/extras/$basearch/ gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7 #additional packages that extend functionality of existing packages [centosplus] name=CentOS-$releasever - Plus #mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus&infra=$infra #baseurl=http://mirror.centos.org/centos/$releasever/centosplus/$basearch/ #baseurl=http://vault.centos.org/7.8.2003/x86_64/os/ baseurl=http://vault.centos.org/7.8.2003/centosplus/$basearch/ gpgcheck=1 enabled=0 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
保存文件
wq
然后再执行命令：
yum clean all yum makecache
最后可以愉快地yum了
