1.安装wget

yum -y install wget

2.下载网易源

cd /etc/yum.repos.d/

wget http://mirrors.163.com/.help/CentOS6-Base-163.repo

3.覆盖自带的源

mv CentOS6-Base-163.repo CentOS-Base.repo

4.更新列表，完成更换

yum clean all
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