打开centos的yum文件夹
输入命令cd /etc/yum.repos.d/
用wget下载repo文件
输入命令wget http://mirrors.aliyun.com/repo/Centos-7.repo
如果wget命令不生效，说明还没有安装wget工具，输入yum -y install wget 回车进行安装。
当前目录是/etc/yum.repos.d/，刚刚下载的Centos-7.repo也在这个目录上
备份
[root@bogon ~]# cd /etc/yum.repos.d/ [root@bogon yum.repos.d]# mkdir repo_bak [root@bogon yum.repos.d]# mv *.repo repo_bak/ [root@bogon yum.repos.d]# ls repo_bak
下载新的CentOS-Base.repo 到/etc/yum.repos.d/
wget -O /etc/yum.repos.d/CentOS-Base.repo
[root@bogon yum.repos.d]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo --2018-02-09 16:33:46-- http://mirrors.aliyun.com/repo/Centos-7.repo Resolving mirrors.aliyun.com (mirrors.aliyun.com)... 124.14.2.234, 124.14.2.235, 124.14.2.217, ... Connecting to mirrors.aliyun.com (mirrors.aliyun.com)|124.14.2.234|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 2573 (2.5K) [application/octet-stream] Saving to: ‘/etc/yum.repos.d/CentOS-Base.repo' 100%[========================================================================================>] 2,573 --.-K/s in 0s 2018-02-09 16:33:47 (182 MB/s) - ‘/etc/yum.repos.d/CentOS-Base.repo' saved [2573/2573] [root@bogon yum.repos.d]# ls CentOS-Base.repo repo_bak
之后运行yum clean all 清除缓存，运行 yum makecache 生成新的缓存
[root@bogon yum.repos.d]# yum clean all Loaded plugins: fastestmirror Cleaning repos: base extras updates Cleaning up everything Maybe you want: rm -rf /var/cache/yum, to also free up space taken by orphaned data from disabled or removed repos Cleaning up list of fastest mirrors [root@bogon yum.repos.d]# yum makecache Loaded plugins: fastestmirror base | 3.6 kB 00:00:00 extras | 3.4 kB 00:00:00 updates | 3.4 kB 00:00:00 (1/12): base/7/x86_64/group_gz | 156 kB 00:00:00 (2/12): extras/7/x86_64/filelists_db | 636 kB 00:00:07 (3/12): extras/7/x86_64/primary_db
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。