ping mi.com
yum update
yum instll wget
wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm 
# 如果上一步无法连接直接去这个网址找：https://dl.fedoraproject.org/pub/epel/
rpm -ivh epel-release-latest-8.noarch.rpm
yum -y install sl