Linux
vi /etc/hosts
最后一行添加你要映射的ip对应的地址
192.168.0.1 cas.demo.com

windows
很多人不知道hosts文件放在哪里？

C:\Windows\System32\drivers\etc

# 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
192.168.0.1     cas.demo.com

使用局域网代理的朋友需要注意：把改网址添加为不需要代理访问。

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