卸载yum
查看：rpm -qa |grep yum
卸载：rpm -aq|grep yum|xargs rpm -e --nodeps
还是无意间执行 yum remove yum卸载了yum，重新安装思路如下：
安装yum
下载RPM包 http://mirrors.163.com/centos/7/os/x86_64/Packages/
centos7 为例：
weget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-urlgrabber-3.10-10.el7.noarch.rpm
weget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-cron-3.4.3-168.el7.centos.noarch.rpm
weget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-168.el7.centos.noarch.rpm
weget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
weget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
rpm -ivh --force --nodeps python-urlgrabber-3.10-10.el7.noarch.rpm
rpm -ivh --force --nodeps yum-cron-3.4.3-168.el7.centos.noarch.rpm
rpm -ivh --force --nodeps yum-3.4.3-168.el7.centos.noarch.rpm
rpm -ivh --force --nodeps yum-metadata-parser-1.1.4-10.el7.x86_64.rpm
rpm -ivh --force --nodeps yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
yum
如果出现
no module named yum
这个问题解决方案：
下载： http://mirrors.163.com/centos/7/os/x86_64/Packages/
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-2.7.5-89.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-chardet-2.2.1-3.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-devel-2.7.5-89.el7.x86_64.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/python-kitchen-1.1.1-5.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-libs-2.7.5-89.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-pycurl-7.19.0-19.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-setuptools-0.9.8-7.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/python-urlgrabber-3.10-10.el7.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/rpm-python-4.11.3-45.el7.x86_64.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-3.4.3-168.el7.centos.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-aliases-1.1.31-54.el7_8.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.31-54.el7_8.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-plugin-protectbase-1.1.31-54.el7_8.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-updateonboot-1.1.31-54.el7_8.noarch.rpm
wget http://mirrors.163.com/centos/7/os/x86_64/Packages/yum-utils-1.1.31-54.el7_8.noarch.rpm
rpm -ivh --force *.rpm --nodeps
然后再yum
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