14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error

1，背景

执行yum install xxx 时，报错：

Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=vag error
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error

2，解决方案

2.1，首先验证网络没问题

ping www.baicu.com

2.2，备份系统自带yum源配置文件

mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.back

2.3，通过curl下载yum源

curl -o /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo

2.4，运行yum makecache生成缓存

yum makecache

2.5，更新yum源，等待完成即可使用yum下载命令

yum -y update