CentOS8 yum install失败

在CentOS8上面用yum安装git的时候遇到如下问题：

[vagrant@192.168.38.4] ~  >> sudo yum install git
CentOS Linux 8 - AppStream                       71  B/s |  38  B     00:00
Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist

尝试利用换镜像源的方案没有作用
linux 为 repo ‘AppStream’ 下载元数据失败

解决方案
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-Linux-*
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-Linux-*

如果想要更新centos8:

sudo dnf install centos-release-stream -y
sudo dnf swap centos-{linux,stream}-repos -y
sudo dnf distro-sync -y