按照网上的做法安装，遇到这个问题
python-urlgrabber >= 3.10-8 is needed by yum-3.4.3-150.el7.centos.noarch
最终解决方案，安装低配的包。
链接：https://pan.baidu.com/s/1b2ObRrvVZO6ZmFXIsrlt5Q 密码：bcqx
1.查看red hat7 自带的yum 软件包
rpm -qa | grep yum
2.卸载这些软件包
3.安装上面低配的包（百度云里的）
rpm -ivh yum-*
4.新建repo 配置文件；
vim /etc/yum.repos.d/CentOS-Base.repo
#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-$7 - Base - 163.com
#mirrorlist=[http://mirrorlist.centos.org/?release=7&arch=<math xmlns="http://www.w3.org/1998/Math/MathML"><merror><mtext>7&arch=</mtext></merror></math>basearch&repo=os](http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=os)
baseurl=[http://mirrors.163.com/centos/7/os/$basearch/](http://mirrors.163.com/centos/7/os/$basearch/)
gpgcheck=1
gpgkey=[http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7](http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7)
#released updates
[updates]
name=CentOS-$7 - Updates - 163.com
#mirrorlist=[http://mirrorlist.centos.org/?release=7&arch=<math xmlns="http://www.w3.org/1998/Math/MathML"><merror><mtext>7&arch=</mtext></merror></math>basearch&repo=updates](http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=updates)
baseurl=[http://mirrors.163.com/centos/7/updates/$basearch/](http://mirrors.163.com/centos/7/updates/$basearch/)
gpgcheck=1
gpgkey=[http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7](http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7)
#additional packages that may be useful
[extras]
name=CentOS-$7 - Extras - 163.com
#mirrorlist=[http://mirrorlist.centos.org/?release=7&arch=<math xmlns="http://www.w3.org/1998/Math/MathML"><merror><mtext>7&arch=</mtext></merror></math>basearch&repo=extras](http://mirrorlist.centos.org/?release=$7&arch=$basearch&repo=extras)
baseurl=[http://mirrors.163.com/centos/7/extras/$basearch/](http://mirrors.163.com/centos/7/extras/$basearch/)
gpgcheck=1
gpgkey=[http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7](http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7)
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$7 - Plus - 163.com
baseurl=[http://mirrors.163.com/centos/7/centosplus/$basearch/](http://mirrors.163.com/centos/7/centosplus/$basearch/)
gpgcheck=1
enabled=0
gpgkey=[http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7](http://mirrors.163.com/centos/RPM-GPG-KEY-CentOS-7)
5.清除缓存
yum clean all
6.yum install bind 测试一下 安装成功
