https://www.cnblogs.com/root-123/p/16570906.html
一、备份原来的yum源,以防后续使用
cd /etc/yum.repos.d/;mkdir bak/; mv *.repo bak/
二、下载阿里云的base源
Centos6:
wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-6.repo
或者:
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-6.repo
Centos7:
wget https://mirrors.aliyun.com/repo/Centos-7.repo
或者:
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-7.repo
Centos:8
wget -O /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-8.repo
或者:
curl -o /etc/yum.repos.d/CentOS-Base.repo https://mirrors.aliyun.com/repo/Centos-8.repo
三、下载阿里云的epel源
wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
四、清除缓存并生成新的缓存
yum clean all && yum makecache
#生成缓存需要时间,可以直接显示当前可用yum源
yum clean all && yum repolist
解决linux不能访问外网的问题
直接放大招,解决方法: cd /etc/sysconfig/network-scripts
vi ifcfg-ens33
修改如图所示处 然后再将之前配置的ipaddr gateway什么的使用#注释掉
最后一步,重启network service network restart ping www.baidu.com