yum 安装时错误 Errno 14 Couldn't resolve host 解决办法

Downloading Packages:

http://mirrors.163.com/centos/6.5/os/i386/Packages/mlocate-0.22.2-4.el6.i686.rpm: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'mirrors.163.com'"Trying other mirror.
http://mirrors.aliyun.com/centos/6.5/os/i386/Packages/mlocate-0.22.2-4.el6.i686.rpm: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'mirrors.aliyun.com'"Trying other mirror.
http://centos.ustc.edu.cn/centos/6.5/os/i386/Packages/mlocate-0.22.2-4.el6.i686.rpm: [Errno 14] PYCURL ERROR 6 - "Couldn't resolve host 'centos.ustc.edu.cn'"Trying other mirror.

后来网上查了一下说是DNS服务器错误。于是修改一下 /etc/resolv.conf

添加一个nameserver 8.8.8.8完成

[root@node4 etc]# cat resolv.conf 
nameserver 8.8.8.8
nameserver 172.28.1.26 
nameserver 172.28.1.28