Centos7.4重装yum

1、查看已安装的yum

[root@mdw opt]# rpm -qa | grep yum
yum-metadata-parser-1.1.4-10.el7.x86_64
yum-3.4.3-161.el7.centos.noarch
yum-plugin-fastestmirror-1.1.31-50.el7.noarch

2、卸载

[root@mdw opt]# rpm -aq|grep yum|xargs rpm -e --nodeps

3、下载yum的rpm包

[root@mdw opt]# cat /etc/redhat-release 
CentOS Linux release 7.4.1708 (Core)

下载网站：http://vault.centos.org/7.4.1708/os/x86_64/Packages/

wget http://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-42.el7.noarch.rpm
wget http://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
wget http://vault.centos.org/7.4.1708/os/x86_64/Packages/yum-3.4.3-154.el7.centos.noarch.rpm
[root@mdw opt]# rpm -ivh yum-*
准备中...                          ################################# [100%]
正在升级/安装...
   1:yum-metadata-parser-1.1.4-10.el7 ################################# [ 33%]
   2:yum-plugin-fastestmirror-1.1.31-4################################# [ 67%]
   3:yum-3.4.3-154.el7.centos         ################################# [100%]

4、修改yum源

cd  /etc/yum.repos.d
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
wget http://mirrors.163.com/.help/CentOS7-Base-163.repo
yum clean all
yum makecache