Centso6
cp /etc/yum.repos.d/CentOS-Base.repo /etc/yum.repos.d/CentOS-Base.repo.ori 拷贝一份源文件
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.163.com .help/CentOS6-Base-163.repo 设置网易连接
