Cisco发现协议

1、 2006, Shenzhen Polytechnic. All rights reserved.1Cisco发现协议发现协议Cisco Discovery Protocol深圳职业技术学院计算机系网络专业深圳职业技术学院计算机系网络专业 2006, Shenzhen Polytechnic. All rights reserved.2教学目标（教学目标（ Objectives ）1. Cisco发现协议特征（发现协议特征（Feature of Cisco Discovery Protocol ） 2.CDP命令（命令（CDP Command ）3.开启和关闭开启和关闭CDP（Enable a

2、nd disable CDP）4. 远程登录（远程登录（telnet ） 2006, Shenzhen Polytechnic. All rights reserved.3Cisco发现协议（发现协议（ Cisco Discovery Protocol ）1.Cisco提供的专有的命令提供的专有的命令CDP runs on all Cisco equipment 2.获得直接连接的设备的信息摘要获得直接连接的设备的信息摘要The primary use of CDP is to discover all Cisco devices that are directly connected to

3、a local device. 3.运行在数据链路层运行在数据链路层Cisco Discovery Protocol (CDP) is a Layer 2 protocol 4.Cdp版本版本1在在10.3版本后会自动启动版本后会自动启动CDP Version 1 is enabled by default with Cisco IOS (Release 10.3 later). 5.cdp更新周期更新周期60秒秒CDP update timer is 60s6.cdp过期周期过期周期180秒秒CDP hold timer is 180s 2006, Shenzhen Polytechnic.

4、 All rights reserved.4信息摘要包括（信息摘要包括（Summary information includes）: 设备设备ID（Device ID） 本地接口（本地接口（Local Interface ） 保持时间（保持时间（Holdtime ） 功能（功能（Capability ） 平台（平台（Platform ） 端口端口ID（Port ID ） VTP域名（域名（VTP Management Domain Name (CDPv2 only) ） 本征本征VLAN（Native VLAN (CDPv2 only) ） 全双工全双工/半双工（半双工（Full/Half-D

5、uplex (CDPv2 only) ）CDPshow cdpCDPCDP用用CDP发现邻居（发现邻居（Discovering Neighbors with CDP） 2006, Shenzhen Polytechnic. All rights reserved.5Using the show cdp neighbor CommandRouterA#sh cdp neighborsCapability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge S - Switch, H - Host, I - IGMP, r -

6、RepeaterDevice ID Local Intrfce Holdtme Capability Platform Port IDRouterB Ser 0 148 R 2522 Ser 1SwitchA Eth 0 167 T S 1900 2 SwitchBRouterARouterBSwitchAS0S1 2006, Shenzhen Polytechnic. All rights reserved.6Using the show cdp entry CommandRouterA#sh c

7、dp entry *-Device ID: RouterB Entry address(es): IP address: Platform: cisco 2522, Capabilities: Router Interface: Serial0, Port ID (outgoing port): Serial1Holdtime : 168 secVersion :Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-JS-L), Version 12.0(3), RELEASE S

8、OFTWARE (fci)Copyright (c) 1986-1999 by cisco Systems, Inc.Compiled Mon 08-Feb-99 18:18 by phanguyeSwitchBRouterARouterBSwitchAS0S1 2006, Shenzhen Polytechnic. All rights reserved.7CDP其它命令（其它命令（Additional CDP Commands）RouterA#sh cdp trafficCDP counters

9、 :Packets output: 56, Input: 38Hdr syntax: 0, Chksum error: 0, Encaps failed: 3No memory: 0, Invalid packet: 0, Fragmented: 0RouterA#sh cdp interface BRI0 is administratively down, line protocol is down Encapsulation HDLC Sending CDP packets every 60 seconds Holdtime is 180 secondsSwitchBRouterARout

10、erBSwitchAS0S1 2006, Shenzhen Polytechnic. All rights reserved.81. 在全局配置模式下使用在全局配置模式下使用（no）cdp run 命令开启命令开启或关闭所由接口的或关闭所由接口的CDP功能。默认情况下，功能。默认情况下，CDP被被全局开启。全局开启。The cdp run command is used to enable CDP globally on the router. By default, CDP is globally

11、 enabled. 2.在接口模式下使用在接口模式下使用（no） cdp enable 命令可以命令可以开启或关闭某个特定接口的开启或关闭某个特定接口的CDP功能。功能。CDP could be enabled on each of the devices interfaces by using the cdp enable command. 开启和关闭开启和关闭CDP（Enable and disable CDP） 2006, Shenzhen Polytechnic. All rights reserved.9配置周期（配置周期（Configuring Timer）Router(confi

12、g)#cdp timer 5Router(config)# cdp holdtime 15 2006, Shenzhen Polytechnic. All rights reserved.10用用telnet连接到远程主机连接到远程主机（Using Telnet to Connect to Remote Devices）Remote deviceSwitchBRouterARouterBSwitchAS0S1RouterA#telnet Trying . Open

13、-Catalyst 1900 Management ConsoleCopyright (c) Cisco Systems, Inc. 1993-1998All rights reserved.Enterprise Edition SoftwareEthernet Address: 00-90-86-73-33-40PCA Number: 73-2239-06PCA Serial Number: FAA02359H8KModel Number: WS-C1924-ENSystem Serial Number: FAA0237X0FQ.RouterB 2006, Shenzhen Polytech

14、nic. All rights reserved.11查看查看telnet连接（连接（Viewing Telnet Connections）SwitchBRouterARouterBSwitchAS0S1RouterA#sh sessionConn Host Address Byte Idle Conn Name 1 0 1 * 2 0 0 RouterA#sh user Line User Ho

15、st(s) Idle Location* 0 con 0 3 2 11 vty 0 idle 1 2006, Shenzhen Polytechnic. All rights reserved.12挂起挂起telnet会话（会话（Suspending a Telnet Session）SwitchBRouterARouterBSwitchAS0S1RouterB# xRouterA#sh sessionConn Host Address Byte

16、 Idle Conn Name 1 0 1 RouterA#resume 1RouterB# 2006, Shenzhen Polytechnic. All rights reserved.13RouterA#disconnect Closing connection to confirmRouterA#clear line 11confirm OK关闭关闭telnet会话（会话（Closing a Telnet Session）Closing a session opened by a remote deviceClosing the current session opened by youSwitchBRouterARouterBSwitchA10