首先删除原来的yum

rpm -aq|grep yum|xargs rpm -e --nodeps

q|grep python-iniparse|xargs rpm -e --nodeps

第二步：下载centos的rpm安装包

wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-154.el7.centos.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-iniparse-0.4-9.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-Metadata-parser-1.1.4-10.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-42.el7.noarch.rpm

第三步：安装rpm包

rpm -ivh *.rpm --nodeps

第五步：新建repo文件，这里命名为rhel.repo,编辑文件，写入下面内容

[base]
name=CentOS-$releasever - Base
baseurl=http://mirrors.163.com/centos/7/os/$basearch/
gpgcheck=1
http://mirrors.163.com/centos/7/os/x86_64/RPM-GPG-KEY-CentOS-7


#released updates
[updates]
name=CentOS-$releasever - Updates
baseurl=http://mirrors.163.com/centos/7/updates/$basearch/
gpgcheck=1
http://mirrors.163.com/centos/7/os/x86_64/RPM-GPG-KEY-CentOS-7

[extras]
name=CentOS-$releasever - Extras
baseurl=http://mirrors.163.com/centos/7/extras/$basearch/
gpgcheck=1
gpgkey=http://mirrors.163.com/centos/7.2.1511/os/x86_64/RPM-GPG-KEY-CentOS-7

[centosplus]
name=CentOS-$releasever - Plus
baseurl=http://mirrors.163.com/centos/7/centosplus/$basearch/
gpgcheck=1
enabled=0

然后执行 yum clear all

yum update 测试