java_网络编程学习笔记(四)

域名解析学习笔记

1 当在浏览器中输入一个访问地址，首先会访问C:\Windows\System32\drivers\etc\hosts文件。

hosts文件:

# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

# localhost name resolution is handled within DNS itself.
#	127.0.0.1       localhost
#	::1             localhost

2 localhost和127.0.0.1不在DNS服务器中，就是在hosts文件中配置。 如果hosts文件没查到，则会到DNS服务器中查询。DNS配置

3 DNS服务器向浏览器返回相应的IP地址。

4 浏览器访问IP +　端口号 f访问相应资源。