ccna課程

1、第五章IP 路由,本章目標,通過本章的學習，您應該掌握以下內(nèi)容： 區(qū)分靜態(tài)、動態(tài)路由的不同設置靜態(tài)路由識別距離矢量的路由協(xié)議：RIP 和 IGRP設置Routing Information Protocol (RIP) 設置Interior Gateway Routing Protocol (IGRP) 利用show 和 debug 命令查看 IP 路由信息,要實現(xiàn)路由路由器必須知道:目的地址源地址所有可能的路由路徑

2、最佳路由路徑管理路由信息,什么是路由,,,,,,,,172.16.1.0,10.120.2.0,,什么是路由,,,,,NetworkProtocol,DestinationNetwork,ConnectedLearned,10.120.2.0172.16.1.0,,Exit Interface,E0S0,可路由協(xié)議: IP,路由器必須知道未和其直接相連的目的地址,,,,,,,,172.16.1.0,10.120.2.0,E

3、0,,,S0,,,靜態(tài)路由由網(wǎng)絡管理員在路由器上手工添加路由信息以實現(xiàn)路由目的,動態(tài)路由根據(jù)網(wǎng)絡結構或流量的變化，路由協(xié)議會自動調(diào)整路由信息以實現(xiàn)路由,靜態(tài)路由和動態(tài)路由,靜態(tài)路由具有以下幾個優(yōu)點：減小了路由器的日常開銷。 在小型互聯(lián)網(wǎng)上很容易配置。 可以控制路由選擇的更新。,靜態(tài)路由,但是，靜態(tài)路由在網(wǎng)絡變化頻繁出現(xiàn)的環(huán)境中并不會很好的工作。在大型的和經(jīng)常變動的互聯(lián)網(wǎng)，配置靜態(tài)路由是不現(xiàn)實。,動態(tài)路由的主要優(yōu)點是，如果存在到

4、目的站點的多條路徑，運行了路由選擇協(xié)議（如RIP或IGRP）之后，而正在進行數(shù)據(jù)傳輸?shù)囊粭l路徑發(fā)生了中斷的情況下，路由器可以自動的選擇另外一條路徑傳輸數(shù)據(jù)。這對于建立一個大型的網(wǎng)絡是一個優(yōu)點。,動態(tài)路由,,,,172.16.2.1,SO,靜態(tài)路由,172.16.1.0,B,172.16.2.2,Network,,,,,A,在小型網(wǎng)絡中適宜設置靜態(tài)路由。,B,Stub Network,,,指定一條可以到達目標網(wǎng)絡的路徑,,Router(c

5、onfig)#ip route network [mask] {address | interface}[distance] [permanent],靜態(tài)路由的配置,,Stub Network,,,ip route 172.16.1.0 255.255.255.0 172.16.2.1,,,172.16.2.1,SO,靜態(tài)路由的例子,172.16.1.0,B,172.16.2.2,Network,,,,,A,B,這是一條單方向的路徑

6、，必須配置一條相反的路徑。,,,,Stub Network,,,,ip route 0.0.0.0 0.0.0.0 172.16.2.2,,,,缺省路由,,172.16.2.1,SO,172.16.1.0,B,172.16.2.2,Network,,,,,A,B,使用缺省路由后，Stub Network可以到達路由器A以外的網(wǎng)絡。,路由協(xié)議,路由協(xié)議 用于路由器選擇路徑和管理路由表。一旦選擇了一條路徑后，路由器將路由可路由協(xié)議 。,,

7、,,,NetworkProtocol,DestinationNetwork,ConnectedRIPIGRP,10.120.2.0172.16.2.0172.17.3.0,,Exit Interface,E0S0S1,可路由協(xié)議: IP路由協(xié)議: RIP, IGRP,,,172.17.3.0,,,,,,,,172.16.1.0,10.120.2.0,E0,,,S0,,自治系統(tǒng) 100,自治系統(tǒng) 200,IGPs: RI

8、P, IGRP,,EGPs: BGP,,自治系統(tǒng)：內(nèi)部和外部的路由協(xié)議,自治系統(tǒng)：使用相同的路由準則的網(wǎng)絡的集合IGP在一個自治系統(tǒng)內(nèi)運行。EGP連接不同的自治系統(tǒng)。,,,,,,,,,,,路由的可信度,IGRPAdministrative Distance=100,Router D,Router B,Router A,Router C,,,RIPAdministrative Distance=120,E,,I need t

9、o send a packet to Network E. Both router B and C will get it there. Which route is best?,,,路由協(xié)議的分類,距離矢量,混合路由,鏈路狀態(tài),,,C,B,,,,,,,,,,,,,,,,A,,D,C,D,B,A,距離矢量的路由協(xié)議,它使用的是最簡單的距離矢量（Distance-Vector，簡稱D-V）路由算法。距離矢量協(xié)議定期直接傳送各自路由表的

10、所有信息給鄰居。網(wǎng)絡中的路由器從自己的鄰居路由器得到路由信息，并將這些路由信息連同自己的本地路由信息發(fā)送給其他鄰居，這樣一級一級地傳遞下去以達到全網(wǎng)同步。每個路由器都不了解整個網(wǎng)絡拓撲，它們只知道與自己直接相連的網(wǎng)絡情況，并根據(jù)從鄰居得到的路由信息更新自己的路由表。它所有的信息都靠道聽途說，它相信所有鄰居告訴它的所有信息，只在這些鄰居中選擇最優(yōu)的來采用，類似于傳話這個游戲。,鏈路狀態(tài)的路由協(xié)議,鏈路狀態(tài)路由協(xié)議是目前使用最廣的一類域內(nèi)路

11、由協(xié)議。它采用一種“拼圖”的設計策略，即每個路由器將它到其周圍鄰居的鏈路狀態(tài)向全網(wǎng)的其他路由器進行廣播。這樣，一個路由器收到從網(wǎng)絡中其他路由器發(fā)送過來的路由信息后，它對這些鏈路狀態(tài)進行拼裝，最終生成一個全網(wǎng)的拓撲視圖，近而可以通過最短路徑算法來計算它到別的路由器的最短路徑。,路由協(xié)議,定期將路由表復制給相鄰的路由器并且進行矢量堆加,,,,,C,D,B,A,,,,,,,,,,,,,,,,,,,,,C,B,A,D,,,RoutingTab

12、le,RoutingTable,RoutingTable,RoutingTable,,Distance—How farVector—In which direction,,,,,路由器從收集到的源信息中選擇到達目標地址的最佳路徑,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,Routing Table,10.2.0.0,10.3.0.0,,,,0,,

13、0,,,,,Routing Table,10.3.0.0,,S0,0,10.4.0.0,,E0,0,,,,,Routing Table,10.1.0.0,10.2.0.0,,,,,,,,0,0,源信息的獲得,,,,,路由器從收集到的源信息中選擇到達目標地址的最佳路徑,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,,,Routing Table,10.1.0.

14、0,10.2.0.0,10.3.0.0,,Routing Table,10.2.0.0,10.3.0.0,10.4.0.0,10.1.0.0,,0,,0,,1,,1,Routing Table,10.3.0.0,,S0,0,10.4.0.0,,E0,0,10.2.0.0,,1,,,,,1,,0,0,源信息的獲得,,,,源信息的獲得,路由器從收集到的源信息中選擇到達目標地址的最佳路徑,,,,,A,B,C,10.1.0.0,10.2.0.0

15、,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,,,Routing Table,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,Routing Table,10.2.0.0,10.3.0.0,10.4.0.0,10.1.0.0,,0,,0,,1,,1,Routing Table,10.3.0.0,,S0,0,10.4.0.0,,E0,0,10.2.0.0,,S0,10.1.0.0,1,2

16、,,,,1,2,0,0,,距離矢量—選擇最佳路徑,用于確定最佳路由路徑的參數(shù)信息,,,,,,,,,,,56,T1,56,T1,B,A,Hop count,RIP,IGRP,,,BandwidthDelayLoadReliabilityMTU,距離矢量—管理路由信息,路由表的更新過程將通過路由器之間一步一步來完成,,A,更新路由表,,距離矢量—管理路由信息,路由表的更新過程將通過路由器之間一步一步來完成,,,A,更新路由表,,,,

17、,距離矢量—管理路由信息,路由表的更新過程將通過路由器之間一步一步來完成,,,,A,,B,更新路由表,更新路由表,,,,,路 由 回 環(huán),每一個節(jié)點管理著與之相連的所有網(wǎng)絡,,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,Routing Table,,,10.3.0.0,,,,,,,S0,E0,S0,S0,,,1,2,10.1.0.0,10.2.0.0,10

18、.4.0.0,0,0,Routing Table,,,10.1.0.0,,,,,,,E0,S0,S0,S0,,,1,2,10.4.0.0,10.3.0.0,10.2.0.0,0,0,Routing Table,,,10.2.0.0,,,,,,,S0,S1,S1,S0,,,1,1,10.1.0.0,10.4.0.0,10.3.0.0,0,0,,,,路 由 回 環(huán),緩慢的收斂容易造成路由信息的不一致,,,,,A,B,C,10.1.0.0,1

19、0.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,Routing Table,,,10.3.0.0,,,,,,,S0,E0,S0,S0,,,1,2,10.1.0.0,10.2.0.0,10.4.0.0,0,Down,Routing Table,,,10.1.0.0,,,,,,,E0,S0,S0,S0,,,1,2,10.4.0.0,10.3.0.0,10.2.0.0,0,0,Routing Tab

20、le,,,10.2.0.0,,,,,,,S0,S1,S1,S0,,,1,1,10.1.0.0,10.4.0.0,10.3.0.0,0,0,,,,路由器C 推斷到達10.4.0.0 網(wǎng)絡的最好路徑是通過路由器B,路 由 回 環(huán),,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,,,路由器 A 根據(jù)錯誤的信息升級它的路由表,路 由 回 環(huán),,,,,A,B,

21、C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,Routing Table,,,,,,,,,,,1,2,0,2,Routing Table,,,,,,,,,,,1,4,0,0,Routing Table,,,,,,,,,,,3,1,0,0,,,,無 限 計 數(shù),10.4.0.0 網(wǎng)絡的數(shù)據(jù)將在路由器 A, B, 和 C 之間循環(huán)10.4.0.0 網(wǎng)絡的跳數(shù)將無限大

22、,,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,Routing Table,,,10.3.0.0,,,,,,,,,1,2,10.1.0.0,10.2.0.0,10.4.0.0,0,4,Routing Table,,,,,,,,,,,1,6,0,0,Routing Table,,,,,,,,,,,5,1,0,0,,,,解決方法：定義最大跳數(shù),指定最大

23、跳數(shù)來防止路由回環(huán),,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,,,,解決方法：水平分割,不會接收到由自身傳達出去的路由信息,,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,X,X,,,,解決方法：路由中毒,路由器將該路由信息的跳數(shù)標記為無限大,,,,,A,B

24、,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,,,解決方法：毒性逆轉(zhuǎn),毒性逆轉(zhuǎn)可以超越水平分割,,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,PoisonReverse,解決方法：Hold-Down 計時,路由器在Hold-Down時間內(nèi)將該條記錄標記為possibly do

25、wn以使其它路由器能夠重新計算網(wǎng)絡結構的變化,Network 10.4.0.0 is downthen back up then back down,Update afterhold-down Time,Network 10.4.0.0is unreachable,,,,,A,B,C,10.1.0.0,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,,Update afterhol

26、d-down Time,解決方法：觸發(fā)更新,當路由表發(fā)生變化時路由器立即發(fā)送更新信息,,,,,A,B,C,10.2.0.0,10.3.0.0,10.4.0.0,E0,S0,S0,S1,S0,E0,X,Network 10.4.0.0is unreachable,,Network 10.4.0.0is unreachable,,Network 10.4.0.0is unreachable,,10.1.0.0,一個完整的方案,,D,B

27、,E,A,X,C,10.4.0.0,,,,一個完整的方案,D,B,E,A,C,X,10.4.0.0,,,Holddown,Holddown,Holddown,,一個完整的方案,D,B,E,A,C,X,10.4.0.0,,,Holddown,Holddown,Holddown,Poison Reverse,Poison Reverse,Poison Reverse,Poison Reverse,,,,一個完整的方案,D,B,E,A,C,X

28、,10.4.0.0,,,Holddown,Holddown,Holddown,Packet for Network 10.4.0.0,Packet for Network 10.4.0.0,,一個完整的方案,D,B,E,A,C,Link up!,10.4.0.0,,,,一個完整的方案,D,B,E,A,C,Link up!,10.4.0.0,,,,,鏈路狀態(tài)協(xié)議,傳遞最佳的路徑信息給其它的路由器,,,,,LSA(LSP)數(shù)據(jù)包,SPF

29、運算,拓補結構數(shù)據(jù),最佳路由信息,,,,,路由表,C,A,D,B,距離矢量和環(huán)狀路由的綜合應用,混 合 路 由,,,選擇基于距離矢量的路徑Converge rapidly using 通過傳遞變化的更新信息達到快速收斂,平衡的路由,,路由器配置選擇路由協(xié)議指定網(wǎng)絡或端口,Network160.89.0.0,,,,Network 172.30.0.0,,IGRP,RIP,Network 172.16.0.0,,,,,

30、RIP,RIP,,IGRP,IP路由的配置任務,指定IP路由協(xié)議,,Router(config)#router protocol [keyword],指定與路由器直接相連的網(wǎng)絡,,Router(config-router)#network network-number,動態(tài)路由配置,,,,,,,,,19.2 kbps,T1,T1,T1,Hop 計算路由器每隔30秒更新最多支持相同hop數(shù)的6條路徑,,,,RIP 概 述,激活RIP協(xié)

31、議,,Router(config)#router rip,,Router(config-router)#network network-number,選擇所能到達的網(wǎng)絡必須是有效的網(wǎng)絡,RIP 配 置,2.3.0.0,RIP 配置舉例,,,2.3.0.0,,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0

32、,A,B,C,192.168.1.0,E0,,,,,,,查看RIP信息,,RouterA#sh ip protocolsRouting Protocol is "rip" Sending updates every 30 seconds, next due in 0 seconds Invalid after 180 seconds, hold down 180, flushed after 240 O

33、utgoing update filter list for all interfaces is Incoming update filter list for all interfaces is Redistributing: rip Default version control: send version 1, receive any version Interface Send Recv

34、Key-chain Ethernet0 1 1 2 Serial2 1 1 2 Routing for Networks: 10.0.0.0 172.16.0.0 Routing Information Sources: Gateway Distance Last Update 10.1.1.2

35、 120 00:00:10 Distance: (default is 120),,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,,,,查看路由表,,RouterA#sh ip routeCodes: C - connected, S -

36、 static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1

37、, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default U - per-user static route, o - ODR T - traffic engineered routeGateway of last resort i

38、s not set 172.16.0.0/24 is subnetted, 1 subnetsC 172.16.1.0 is directly connected, Ethernet0 10.0.0.0/24 is subnetted, 2 subnetsR 10.2.2.0 [120/1] via 10.1.1.2, 00:00:07, Serial2C 10.1.1.0

39、 is directly connected, Serial2R 192.168.1.0/24 [120/2] via 10.1.1.2, 00:00:07, Serial2,,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,debug ip rip 命令,

40、,,,,,,RouterA#debug ip ripRIP protocol debugging is onRouterA#00:06:24: RIP: received v1 update from 10.1.1.2 on Serial200:06:24: 10.2.2.0 in 1 hops00:06:24: 192.168.1.0 in 2 hops00:06:33: RIP: sending v1

41、 update to 255.255.255.255 via Ethernet0 (172.16.1.1)00:06:34: network 10.0.0.0, metric 100:06:34: network 192.168.1.0, metric 300:06:34: RIP: sending v1 update to 255.255.255.255 via Serial2 (10.1.1.1)00:0

42、6:34: network 172.16.0.0, metric 1,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,使用IGRP的網(wǎng)絡較大缺省100hops，最大255hops支持多路徑,IGRP 介 紹,IGRP,,帶寬延遲時間可靠性負載

43、最大傳輸單元,,19.2 kbps,19.2 kbps,IGRP 路徑選擇,,,,,,,Source,Destination,,,,最多六條路徑下一次所要到達的路由器必須接近目的網(wǎng)絡在允許的參數(shù)內(nèi)選擇路徑,,,,,,,New Route,,,,Initial Route,,,Source,,Destination,,IGRP 的不平衡路徑,,,配 置 IGRP,,Router(config-router)#network net

44、work-number,指定可以到達的網(wǎng)絡,,,Router(config)#router igrp autonomous-system,指定IGRP為IP路由協(xié)議,,,配置 IGRP (續(xù)),,Router(config-router)#traffic-share { balanced | min },控制負載平衡數(shù)據(jù)的分布,,,Router(config-router)#variance multiplier,控制IGRP的負載平

45、衡,,router igrp 100network 172.16.0.0network 10.0.0.0,IGRP 配置舉例,,,router igrp 100network 10.0.0.0,,,router igrp 100network 192.168.1.0network 10.0.0.0,,Autonomous System = 100,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1

46、.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,查看 IGRP 信息,,,,,,RouterA#sh ip protocolsRouting Protocol is "igrp 100" Sending updates every 90 seconds, next due in 21 seconds Invalid

47、 after 270 seconds, hold down 280, flushed after 630 Outgoing update filter list for all interfaces is Incoming update filter list for all interfaces is Default networks flagged in outgoing updates Default networ

48、ks accepted from incoming updates IGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0 IGRP maximum hopcount 100 IGRP maximum metric variance 1 Redistributing: igrp 100 Routing for Networks: 10.0.0.0 172.16.

49、0.0 Routing Information Sources: Gateway Distance Last Update 10.1.1.2 100 00:01:01 Distance: (default is 100),,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S

50、3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,,,查看IP路由表,,,,RouterA#sh ip routeCodes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

51、 N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default

52、 U - per-user static route, o - ODR T - traffic engineered routeGateway of last resort is not set 172.16.0.0/24 is subnetted, 1 subnetsC 172.16.1.0 is directly connected, Ethernet0 10.0.0.

53、0/24 is subnetted, 2 subnetsI 10.2.2.0 [100/90956] via 10.1.1.2, 00:00:23, Serial2C 10.1.1.0 is directly connected, Serial2I 192.168.1.0/24 [100/91056] via 10.1.1.2, 00:00:23, Serial2,,172.16.1.1,S2,E0,

54、S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,,debug ip igrp transaction 命令,,,,,RouterA#debug ip igrp transactionsIGRP protocol debugging is onRouterA#00:21:06: IGRP: se

55、nding update to 255.255.255.255 via Ethernet0 (172.16.1.1)00:21:06: network 10.0.0.0, metric=8895600:21:06: network 192.168.1.0, metric=9105600:21:07: IGRP: sending update to 255.255.255.255 via Serial2 (1

56、0.1.1.1)00:21:07: network 172.16.0.0, metric=110000:21:16: IGRP: received update from 10.1.1.2 on Serial200:21:16: subnet 10.2.2.0, metric 90956 (neighbor 88956)00:21:16: network 192.168.1.0, metric

57、 91056 (neighbor 89056),,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,,debug ip igrp events 命令,,,,,RouterA#debug ip igrp eventsIGRP event debugging is on

58、RouterA#00:23:44: IGRP: sending update to 255.255.255.255 via Ethernet0 (172.16.1.1)00:23:44: IGRP: Update contains 0 interior, 2 system, and 0 exterior routes.00:23:44: IGRP: Total routes in update: 200:23:44: IGRP

59、: sending update to 255.255.255.255 via Serial2 (10.1.1.1)00:23:45: IGRP: Update contains 0 interior, 1 system, and 0 exterior routes.00:23:45: IGRP: Total routes in update: 100:23:48: IGRP: received update from 10.1.

60、1.2 on Serial200:23:48: IGRP: Update contains 1 interior, 1 system, and 0 exterior routes.00:23:48: IGRP: Total routes in update: 2,,172.16.1.1,S2,E0,S3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1

61、.0,A,B,C,192.168.1.0,E0,,,路由信息更新舉例,,,,,RouterA# debug ip igrp trans00:31:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0, changed state to down00:31:15: IGRP: edition is now 300:31:15: IGRP: sending upda

62、te to 255.255.255.255 via Serial2 (10.1.1.1)00:31:15: network 172.16.0.0, metric=429496729500:31:16: IGRP: Update contains 0 interior, 1 system, and 0 exterior routes.00:31:16: IGRP: Total routes in update: 100

63、:31:16: IGRP: broadcasting request on Serial200:31:16: IGRP: received update from 10.1.1.2 on Serial200:31:16: subnet 10.2.2.0, metric 90956 (neighbor 88956)00:31:16: network 172.16.0.0, metric 4294967295

64、(inaccessible)00:31:16: network 192.168.1.0, metric 91056 (neighbor 89056)00:31:16: IGRP: Update contains 1 interior, 2 system, and 0 exterior routes.00:31:16: IGRP: Total routes in update: 3,,172.16.1.1,S2,E0,S

65、3,,,,192.168.1.1,10.1.1.1,10.2.2.2,10.1.1.2,S2,S3,10.2.2.3,172.16.1.0,A,B,C,192.168.1.0,E0,,X,,路由信息更新舉例,,,,RouterB#debug ip igrp transIGRP protocol debugging is onRouterB#1d19h: IGRP: sending update to 255.255.255.255

66、 via Serial2 (10.1.1.2)1d19h: subnet 10.2.2.0, metric=889561d19h: network 192.168.1.0, metric=890561d19h: IGRP: sending update to 255.255.255.255 via Serial3 (10.2.2.2)1d19h: subnet 10.1.1.0, metric

67、=889561d19h: network 172.16.0.0, metric=890561d19h: IGRP: received update from 10.1.1.1 on Serial21d19h: network 172.16.0.0, metric 4294967295 (inaccessible)1d19h: IGRP: edition is now 101d19h: IGRP: sen

68、ding update to 255.255.255.255 via Serial2 (10.1.1.2)1d19h: subnet 10.2.2.0, metric=889561d19h: network 172.16.0.0, metric=42949672951d19h: network 192.168.1.0, metric=890561d19h: IGRP: sending upda