Cisco - Small Network Topology (DNS, DHCP, Web Server, Wireless Router)

==路由器

定义：连接两个或多个网络的硬件设备
作用：路由寻址[传送门]

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DHCP服务器

定义：动态主机配置协议（Dynamic Host Configuration Protocol）[传输门]
作用;主要作用是集中地管理、分配IP地址,使网络环境中的主机动态的获得IP地址、Gateway地址、DNS服务器地址等信息.
工作原理：DHCPThe server will create an address pool（地址仓库）,If required by the computer connected to the current serverip地址,It will be given in the form of leaseip地址,The default rental period is one day（serve at homeDHCPThe server is usually a router）,If the rental time is up,It will detect if the computer continues to connect,如果没有就回收,In this connection will be preferredip.

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DNS服务器

定义：域名解析系统（Domain Name System,缩写：DNS）
===作用：
①存储域名&IP地址信息
www.baidu.com <—> 14.215.177.38
②解析(翻译)域名和ip地址
正向解析（The general website only does forward parsing）
www.baidu.com →14.215.177.38
反向解析
14.215.177.38 →www.baidu.com

DNSis a public service
①：DNSThe service that provides analysis is provided by some Internet companies（百度,阿里巴巴,114平台）
②：Each computer has its own recordsDNS的文件
C:\Windows\System32\drivers\etc\hosts

常见公共DNS服务器
常用公共DNS服务器地址
How to set which one the computer usesDNS服务器

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CiscoRouter operating mode

Small network topology

需求：
①：Configure the above equipment reasonablyIPThe address implements the function of each device（网站服务器、dns服务器、DHCP服务器、台式电脑、无线路由器、无线笔记本）
②：The above devices are configured to achieve communication.

建立网络拓扑

配置路由器

配置路由器两端口,Make the left segment192.168.100.Right network segment8.8.8..

①：f0/0 端口 192.168.100.254
②：f0/1 端口 8.8.8.254

Router>en
Router#config
Configuring from terminal, memory, or network [terminal]? 
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#in f0/0
Router(config-if)#ip add 192.168.100.254 255.255.255.0
Router(config-if)#no shut
Router(config-if)#in f0/1
Router(config-if)#ip add 8.8.8.254 255.0.0.0
Router(config-if)#no shut

配置网站服务器

配置如下IP地址,子网掩码,默认网关.
开启http服务,Test for local access.

配置DNS服务器

配置DHCP服务器

配置如下ip地址,子网掩码,网关

配置DHCP服务

Test whether and DNS,Web server communication

Let the hosts in the LAN obtain it automaticallyIP配置

DHCP服务器配置完成后,Hosts in the local area network can be automatically obtainedip配置,No need to get it manually.

Test whether the host can access the website

使用主机1通过IPThe address to access the web server page8.8.8.9
使用主机1Access web server web pages through a domain namewww.web.com

测试通信

使用IP地址访问网站

Use the domain address to access the website

测试结果成功

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无线路由器配置

设定网关地址192.168.1.254 255.255.255.0
Wireless router hasDHCP服务功能,勾选启用DHCP服务器功能

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无线路由器具有ip地址,192.168.100.5 255.255.255.0

Devices connected to the wireless router form a local area network192.168.1.* 24
And can communicate with the outside normally