vi /etc/profile
http_proxy=http://172.20.188.193:3128/
https_proxy=https://172.20.188.193:3128/
export http_proxy
export https_proxy
然后刷新一下 sorce /etc/profile
/etc/yum.conf
配置
http_proxy=http://172.20.188.193:3128/
https_proxy=https://172.20.188.193:3128/
原文：https://www.cnblogs.com/zhangzhiqin/p/11965151.html