- 从网上得知 /etc/resolv.conf中的DNS配置是从/etc/resolvconf/resolv.conf.d/head中加载而来,所以每回改resolv.conf都会失效，在此文件里面已经有说明
打开/etc/resolv.conf内容如下：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
内容是一段警告：说这个文件是resolvconf程序动态创建的，不要直接手动编辑，修改将被覆盖。所以我们不能直接修改这个文件了
- 查资料得到两种方法：
###方法1：
sudo vim /etc/network/interfaces
dns-nameservers 8.8.8.8
###方法2：（这个文件默认是空的）
sudo vim /etc/resolvconf/resolv.conf.d/base
nameserver 8.8.8.8
nameserver 8.8.4.4
如果有多个DNS就一行一个
修改好保存，然后执行
resolvconf -u
sudo vim /etc/resolvconf/resolv.conf.d/head
- 再看/etc/resolv.conf，最下面就多了2行
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
nameserver 8.8.8.8 nameserver 8.8.4.4
现在此DNS已经生效了，无需重启，当然重启也不会丢失
此外还有一种方法是修改/etc/resolvconf/resolv.conf.d/headsudo vim /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
这个文件里提示不要手动修改。。。按照系统提示的说法，不建议改此文件