-bash: yum: command not found

1、虚拟机安装后第一步先挂载mount /dev/cdrom /mnt
如果挂载出错可以关机再启动
2、备份
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.bak
3、再装wget
rpm -ivh /mnt/Packages/wget-1.12-8.el6.x86_64.rpm
4、下载新的CentOS-Base.repo 到/etc/yum.repos.d/
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo
5、之后运行yum makecache生成缓存

真实服务器有时候系统自带wget,也不用挂载，直接执行下两布就OK：
mv /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.backup
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo

 

 

-bash: yum: command not found 错误

 

             在学习Linux时，误把yum命令给删除了，在百度了好几篇文章，但没能解决……............

查看有无 yum安装包 ，有的话卸载：

查看：rpm -qa |grep yum

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

第一步： 到这个网站去下载如下RPM包 ：http://mirrors.163.com/centos/6/os/x86_64/Packages/

cd /etc/yum.repo.d/
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/python-urlgrabber-3.9.1-11.el6.noarch.rpm
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-3.2.29-81.el6.centos.noarch.rpm
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-cron-3.2.29-81.el6.centos.noarch.rpm
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
wget http://mirrors.163.com/centos/6/os/x86_64/Packages/yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm

第二步：下载完成后安装：
rpm -ivh --force --nodeps python-urlgrabber-3.9.1-11.el6.noarch.rpm
rpm -ivh --force --nodeps yum-metadata-parser-1.1.2-16.el6.x86_64.rpm
rpm -ivh --force --nodeps yum-plugin-fastestmirror-1.1.30-41.el6.noarch.rpm yum-3.2.29-81.el6.centos.noarch.rpm

注意：注意最后两个包必需同时安装，否则会相互依赖 

第三步：下载阿里云的yum源：

wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-6.repo  

 

下载以后生成缓存，命令：

yum makecache 

 

如果有提示错误，[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found"

运行下面的命令：

sed -i 's/\$releasever/6/' CentOS-Base.repo

备注：把文件里的$releasever替换为6

 

最后：重新生成缓存，数字不为0，就OK了：

yum clean all

yum makecache

 

好了，就到这了