/etc/resolv.conf里面设置的nameserver就被清空

#cat/etc/resolv.conf
#Dynamicresolv.conf(5)fileforglibcresolver(3)generatedbyresolvconf(8)

#DONOTEDITTHISFILEBYHAND--YOURCHANGESWILLBEOVERWRITTEN注意看：

1/etc/resolv.conf其实是一个Link

它其实指向的是/run/resolvconf/resolv.conf

3如果想自己定义nameserver，那么有以下2个办法：

A在网卡的配置文件/etc/network/interfaces里面加：

dns-nameservers192.168.3.45192.168.8.10

dns-searchfoo.orgbar.com

重启网络

sudoservicenetworkingrestart 或者 sudo/etc/init.d/networkingrestart
也可以重启网卡

sudoifconfigeth0downsudoifconfigeth0up

B修改resolvconf服务的配置文件:/etc/resolvconf/resolv.conf.d/base

echo"searchtest.com">>/etc/resolvconf/resolv.conf.d/base
echo"nameserver202.106.0.20">>/etc/resolvconf/resolv.conf.d/base
这样，在机器重启或resolvconf服务重启都可以保证配置会写到/etc/resolv.conf里面

重启resolvconf服务

serviceresolvconfrestart

A比B的优先级更高,,不过可能会断网.

摘至：http://blog.csdn.net/liangdsh/article/details/70256039