之前因为不小心删除了cetos下的yum和python。现在需要重新安装。网上搜索了一些方法，这里总结了一下。亲测有效

一、卸载(如果安装了，没安装直接看第二步)

1、删除现有的python

rpm -qa|grep python|xargs rpm -ev –allmatches –nodeps ##强制清除已安装的程序及其关联

whereis python |xargs rm -frv ##删除所有残余文件 ##xargs，允许你对输出执行其他某些命令

whereis python ##验证删除，返回无结果说明清除干净

2、删除现有的yum

rpm -qa|grep yum|xargs rpm -ev –allmatches –nodeps

whereis yum |xargs rm -frv

二、安装

1、检查CentOS 7版本

cat /etc/centos-release

2、在 https://vault.centos.org/ 上根据自己版本查找对应的目录

    比如我的是：https://vault.centos.org/7.4.1708/os/x86_64/Packages/

3、下载相应的包

   页面直接搜索下面的名字

python-2.7.5

python-iniparse

python-libs

python-pycurl

python-urlgrabber

rpm-python

yum-3.4.3

yum-metadata-parser

yum-plugin-fastestmirror

然后右键复制链接

  在centos下 下载

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/python-2.7.5-58.el7.x86_64.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/python-iniparse-0.4-9.el7.noarch.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/python-libs-2.7.5-58.el7.x86_64.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/python-pycurl-7.19.0-19.el7.x86_64.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/python-urlgrabber-3.10-8.el7.noarch.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/rpm-python-4.11.3-25.el7.x86_64.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-3.4.3-154.el7.centos.noarch.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm

wget  https://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-42.el7.noarch.rpm

5、安装

全部下载完后，安装

rpm -Uvh --replacepkgs python*.rpm

rpm -Uvh --replacepkgs rpm-python*.rpm yum*.rpm --nodeps --force

三、验证

 安装成功