通过ubuntu等Linux系统都是通过resolve.conf文件进行域名解析的，通过man resolve.conf可以查看到：

The

resolver is a set of routines in the C library that provide access to

the Internet Domain Name System (DNS).  The  resolver

configuration file  contains  information  that  is read by the resolver

routines the first time they are invoked by a process.  The file is

designed  to  be human readable and contains a list of keywords with

values that provide various types of resolver information. If this file

doesn't exist the only name server to be queried  will  be       on

the  local machine; the domain name is determined from the hostname and

the domain search path is constructed from the domain name.

所以DNS解析是由C库函数进行解析的，在Android中bionic/libc/docs/overview.txt文件中我们也可以看到：

NS resolver:

Bionic uses a NetBSD-derived resolver library which has been modified in the following ways:

- don't implement the name-server-switch feature (a.k.a. )

- read /system/etc/resolv.conf instead of /etc/resolv.conf

- read the list of servers from system properties. the code looks for

'net.dns1', 'net.dns2', etc.. Each property should contain the IP

address of a DNS server.

these properties are set/modified by other parts of the Android system (e.g. the dhcpd daemon).

the implementation also supports per-process DNS server list, using

the properties 'net.dns1.', 'net.dns2.', etc...

Where stands for the numerical ID of the current process.

- when performing a query, use a properly randomized Query ID (instead of a incremented one), for increased security.

- when performing a query, bind the local client socket to a random port for increased security.

- get rid of *many* unfortunate thread-safety issues in the original code

Bionic does *not* expose implementation details of its DNS resolver;

the content of is intentionally blank. The

resolver implementation might change completely in the future.

所以android关注的是resolv.conf以及net.dns1等属性。

通

过adb shell中通过getprop查看属性，确实有net.dns1、net.dns2以及wifi中的net.tiwlan0.dns1以及

net.tiwlan0.dns2，移动网络中的net.rmnet0.dns1以及net.rmnet0.dns2等属性。