CentOS更换yum源

# cd /etc/yum.repos.d

#备份默认yum源

# cp CentOS-Base.repo CentOS-Base.repo_bak

#下载网易源，阿里源不行，至少现在很垃圾

# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.163.com/.help/CentOS7-Base-163.repo

#清除系统所有yum源

# yum clean all

#生成yum缓存

# yum makecache

#安装epel源

# yum list | grep epel-release.noarch

# yum install epel-release.noarch

#查看系统可用的yum源

# yum repolist enabled

# yum repolist all