本节内容：
Ubuntu 12.10 DNS配置方法
首先，不推荐修改/etc/resolv.conf或/etc/resolvconf/resolv.conf.d/目录下的head，base文件，添加tail文件的方法，也是不推荐的。
因为resolv.conf和head文件中都有提醒文字：
cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
cat /etc/resolvconf/resolv.conf.d/head
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
以上提示，网络服务一重启，又不行了。
用man resolvconf命令查看文档，可以看到一段提醒注意的文字：
N.B.: On a machine where resolvconf has just been or is about to be installed and which previously relied on a static /etc/resolv.conf file, the nameserver informa