路由ospf的配置

1、it education & trainingdate: 24 october 2021計算機系 鄒瑞源計算機網(wǎng)絡(luò)互聯(lián)技術(shù) it education & trainingdate: 24 october 2021 ospf簡介 ospf是一種典型的鏈路狀態(tài)路由協(xié)議。采用ospf的路由器彼此交換并保存整個網(wǎng)絡(luò)的鏈路信息，從而掌握全網(wǎng)的拓撲結(jié)構(gòu)，獨立計算路由。 ospf作為一種內(nèi)部網(wǎng)關(guān)協(xié)議（interior gateway protocol，igp），用于在同一個自治域（as）中的路由器之間發(fā)布路由信息。區(qū)別于距離矢量協(xié)議(rip)，ospf具有支持大型網(wǎng)絡(luò)、路由收斂快、占用網(wǎng)絡(luò)資

2、源少等優(yōu)點，在目前應(yīng)用的路由協(xié)議中占有相當重要的地位。it education & trainingdate: 24 october 2021ospf簡介開放的國際標準開放的國際標準shortest path first (spf最短路徑優(yōu)先最短路徑優(yōu)先) 算法算法鏈路狀態(tài)路由協(xié)議鏈路狀態(tài)路由協(xié)議it education & trainingdate: 24 october 2021ospf 概述 通過交換hello數(shù)據(jù)包來創(chuàng)建鄰居關(guān)系 以傳播lsa（ link-state advertisements ）代替路由表更新. 鏈路（link）：路由器接口 狀態(tài)（state）：描述

3、接口以及它與鄰居路由器的關(guān)系 lsas 泛洪到區(qū)域中的所有ospf路由器，而不僅僅是直連路由器 收集由ospf路由器生成的所有l(wèi)sa以創(chuàng)建ospf鏈路狀態(tài)數(shù)據(jù)庫. 使用spf算法計算到每個目的地的最短距離，并將其置于路由表中.it education & trainingdate: 24 october 2021ospf術(shù)語it education & trainingdate: 24 october 2021shortest path first algorithm 將每臺路由器放置在樹的根節(jié)點，并根據(jù)累計開銷計算到將每臺路由器放置在樹的根節(jié)點，并根據(jù)累計開銷計算到達每個目的

4、地的最短路徑達每個目的地的最短路徑 開銷（開銷（cost） = 參考帶寬（參考帶寬（108）/接口帶寬接口帶寬 (bps)it education & trainingdate: 24 october 2021ospf特點詳介特點詳介ospfopen shortest path first 使用cost（成本）作為其路由度量值，其默認成本基于介質(zhì)的傳輸帶寬來度量it education & trainingdate: 24 october 2021ospf特點詳介特點詳介三大優(yōu)越性： 1、收斂時間快 2、支持vlsm和cidr 3、網(wǎng)絡(luò)的擴展性強 對跳數(shù)基本沒有限制，對于跳數(shù)過

5、多的網(wǎng)絡(luò)可通過層次化的設(shè)計，將達的ospf網(wǎng)絡(luò)化分成小的、易管理的ospf域it education & trainingdate: 24 october 2021ospf 層級示列 區(qū)域和自治系統(tǒng)區(qū)域和自治系統(tǒng) 盡量減少路由表條目盡量減少路由表條目 使拓撲變化僅影響本區(qū)域內(nèi)部使拓撲變化僅影響本區(qū)域內(nèi)部it education & trainingdate: 24 october 2021ospf數(shù)據(jù)包類型（ospf packet types）it education & trainingdate: 24 october 2021 ospf 的五種分組類型 類型類型1，

6、問候，問候(hello)分組。分組。類型類型2，數(shù)據(jù)庫描述，數(shù)據(jù)庫描述(database description)分組。分組。類型類型3，鏈路狀態(tài)請求，鏈路狀態(tài)請求(link state request)分組。分組。類型類型4，鏈路狀態(tài)更新，鏈路狀態(tài)更新(link state update)分組，分組， 用洪泛法對全網(wǎng)更新鏈路狀態(tài)。用洪泛法對全網(wǎng)更新鏈路狀態(tài)。類型類型5，鏈路狀態(tài)確認，鏈路狀態(tài)確認(link state acknowledgment) 分組。分組。 it education & trainingdate: 24 october 2021ospf操作操作 1. 建立鄰接關(guān)

7、系2. 必要的進行dr選舉3. 發(fā)現(xiàn)路由4. 選擇相應(yīng)的路由5. 維護路由信息it education & trainingdate: 24 october 2021建立鄰接關(guān)系建立鄰接關(guān)系*標記的在鄰居路由器上必須匹配標記的在鄰居路由器上必須匹配it education & trainingdate: 24 october 2021ospf網(wǎng)絡(luò)類型network typenetwork typecharacteristicscharacteristicsdr/bdr elected?dr/bdr elected?以太網(wǎng)（以太網(wǎng)（ethernetethernet）yes幀中繼（

8、幀中繼（frame relayframe relay）yesppp, hdlcppp, hdlcno管理員用子接口配置（管理員用子接口配置（configured by administrator configured by administrator with subinterfaceswith subinterfaces）noframe relayx.25廣播broadcast multiaccess非廣播nonbroadcast multiaccess點到點point-to-point點到多點point-to-multipointit education & trainingdat

9、e: 24 october 2021點到點鏈路（point-to-point links）不進行dr選舉ospf自動檢測這種接口類型it education & trainingdate: 24 october 2021廣播型多路訪問網(wǎng)絡(luò)進行dr選舉鄰居只與dr和dbr形成鄰接關(guān)系it education & trainingdate: 24 october 2021必要時進行dr選舉 dr與bdr的選舉取決于路由器的優(yōu)先級 可通過接口配置模式 ip ospf priority 命令修改該路由器的優(yōu)先級 如果優(yōu)先級相同，則比較router id。 router id： 默認值：

10、ospf過程啟動時活動接口上的最高ip地址 可以使用環(huán)回接口覆蓋：環(huán)回接口的最高ip地址（次優(yōu)先） 可以使用router-id命令手動設(shè)置（最優(yōu)先）it education & trainingdate: 24 october 2021選舉dr和bdr最高接口優(yōu)先級的路由器被選成dr最高路由器id的路由器被選舉成drdr選舉不具有搶占性it education & trainingdate: 24 october 2021建立雙向通信建立雙向通信it education & trainingdate: 24 october 2021建立雙向通信it education

11、& trainingdate: 24 october 2021建立雙向通信it education & trainingdate: 24 october 2021建立雙向通信it education & trainingdate: 24 october 2021查找網(wǎng)絡(luò)路由it education & trainingdate: 24 october 2021查找網(wǎng)絡(luò)路由it education & trainingdate: 24 october 2021增加鏈路狀態(tài)條目it education & trainingdate: 24 octob

12、er 2021增加鏈路狀態(tài)條目it education & trainingdate: 24 october 2021增加鏈路狀態(tài)條目it education & trainingdate: 24 october 2021維護路由信息路由器用路由器用224.0.0.6通知通知dr it education & trainingdate: 24 october 2021維護路由信息dr利用組播地址利用組播地址224.0.0.5通知其它路由器通知其它路由器it education & trainingdate: 24 october 2021維護路由信息it edu

13、cation & trainingdate: 24 october 2021維護路由信息it education & trainingdate: 24 october 2021配置單區(qū)域的ospfrouter(config-router)# network address wildcard-mask area area-id 將網(wǎng)絡(luò)分配到將網(wǎng)絡(luò)分配到ospf 區(qū)域區(qū)域router(config)# router ospf process-id 將將 ospf定義為定義為 ip 路由協(xié)議路由協(xié)議it education & trainingdate: 24 october

14、 2021ospf 配置示列it education & trainingdate: 24 october 2021ospf配置實例it education & trainingdate: 24 october 2021驗證ospf 配置router# show ip protocols 檢驗是否已配置檢驗是否已配置ospfrouter# show ip route 顯示路由器所學習到的所有路由顯示路由器所學習到的所有路由router# show ip routecodes: i - igrp derived, r - rip derived, o - ospf derived

15、, c - connected, s - static, e - egp derived, b - bgp derived, e2 - ospf external type 2 route, n1 - ospf nssa external type 1 route, n2 - ospf nssa external type 2 route gateway of last resort is 10.119.254.240 to network 10.140.0.0 o e2 10.110.0.0 160/5 via 10.119.254.6, 0:01:00, ethernet2 e 10.67

16、.10.0 200/128 via 10.119.254.244, 0:02:22, ethernet2 o e2 10.68.132.0 160/5 via 10.119.254.6, 0:00:59, ethernet2 o e2 10.130.0.0 160/5 via 10.119.254.6, 0:00:59, ethernet2 e 10.128.0.0 200/128 via 10.119.254.244, 0:02:22, ethernet2 . . .it education & trainingdate: 24 october 2021router# show ip

17、 ospf驗證ospf 配置 顯示顯示ospf路由器、計時器和統(tǒng)計信息路由器、計時器和統(tǒng)計信息router# show ip ospfrouting process ospf 1 with id 172.16.6.1 start time: 00:38:41.540, time elapsed: 00:00:25.860 supports only single tos(tos0) routes supports opaque lsa supports link-local signaling (lls) supports area transit capability router is n

18、ot originating router-lsas with maximum metric initial spf schedule delay 5000 msecsarea backbone(0) (inactive) number of interfaces in this area is 1 area has no authentication spf algorithm last executed 00:00:07.368 ago spf algorithm executed 1 times.it education & trainingdate: 24 october 20

19、21router# show ip ospf interface驗證ospf 配置 顯示區(qū)域顯示區(qū)域 id 和鄰接信息和鄰接信息router# show ip ospf interface ethernet 0 ethernet 0 is up, line protocol is up internet address 192.168.254.202, mask 255.255.255.0, area 0.0.0.0 as 201, router id 192.168.99.1, network type broadcast, cost: 10 transmit delay is 1 sec,

20、 state other, priority 1 designated router id 192.168.254.10, interface address 192.168.254.10 backup designated router id 192.168.254.28, interface addr 192.168.254.28 timer intervals configured, hello 10, dead 60, wait 40, retransmit 5 hello due in 0:00:05 neighbor count is 8, adjacent neighbor co

21、unt is 2 adjacent with neighbor 192.168.254.28 (backup designated router) adjacent with neighbor 192.168.254.10 (designated router) it education & trainingdate: 24 october 2021驗證ospf 配置router# show ip ospf neighbor顯示每個接口上的顯示每個接口上的ospf鄰居信息鄰居信息router# show ip ospf neighbor id pri state dead time a

22、ddress interface 10.199.199.137 1 full/dr 0:00:31 192.168.80.37 ethernet0 172.16.48.1 1 full/drother 0:00:33 172.16.48.1 fddi0 172.16.48.200 1 full/drother 0:00:33 172.16.48.200 fddi0 10.199.199.137 5 full/dr 0:00:33 172.16.48.189 fddi0 it education & trainingdate: 24 october 2021驗證ospf 配置router

23、# show ip ospf neighbor 10.199.199.137 neighbor 10.199.199.137, interface address 192.168.80.37 in the area 0.0.0.0 via interface ethernet0 neighbor priority is 1, state is full options 2 dead timer due in 0:00:32 link state retransmission due in 0:00:04 neighbor 10.199.199.137, interface address 17

24、2.16.48.189 in the area 0.0.0.0 via interface fddi0 neighbor priority is 5, state is full options 2 dead timer due in 0:00:32 link state retransmission due in 0:00:03 router# show ip ospf neighbor detail neighbor 192.168.5.2, interface address 10.225.200.28 in the area 0 via interface gigabitetherne

25、t1/0/0 neighbor priority is 1, state is full, 6 state changes dr is 10.225.200.28 bdr is 10.225.200.30 options is 0 x42 lls options is 0 x1 (lr), last oob-resync 00:03:08 ago dead timer due in 00:00:36 neighbor is up for 00:09:46 index 1/1, retransmission queue length 0, number of retransmission 1 f

26、irst 0 x0(0)/0 x0(0) next 0 x0(0)/0 x0(0) last retransmission scan length is 1, maximum is 1 last retransmission scan time is 0 msec, maximum is 0 msec it education & trainingdate: 24 october 2021ospf 調(diào)試命令router# debug ip ospf eventsospf:hello with invalid timers on interface ethernet0hello inte

27、rval received 10 configured 10net mask received 255.255.255.0 configured 255.255.255.0dead interval received 40 configured 30router# debug ip ospf packet ospf: rcv. v:2 t:1 l:48 rid:200.0.0.117 aid:0.0.0.0 chk:6ab2 aut:0 auk: router# debug ip ospf packet ospf: rcv. v:2 t:1 l:48 rid:200.0.0.116 aid:0

28、.0.0.0 chk:0 aut:2 keyid:1 seq:0 x0it education & trainingdate: 24 october 2021實驗環(huán)境ab192.168.1.64/27192.168.1.32/27192.168.1.104/29it education & trainingdate: 24 october 2021ospf的基本配置router_a#config terminalrouter_a（config）#router_a（config）#router ospf 1 /啟動ospf協(xié)議，其進程為1 router_a（config-rout

29、er）#network 192.168.1.32 0.0.0.31 area 0router_a（config-router）#network 192.168.1.64 0.0.0.31 area 0it education & trainingdate: 24 october 2021router_b#config terminalrouter_b（config）#router_b（config）#router ospf 1 /啟動ospf協(xié)議，其進程為1 router_b（config-router）#network 192.168.1.32 0.0.0.31 area 0rout

30、er_b（config-router）#network 192.168.1.104 0.0.0.7 area 0it education & trainingdate: 24 october 2021ospf身份驗證 ospf支持以下幾種類型的身份驗證： -空（無身份驗證） -明文（或簡單）口令身份驗證 -md5身份驗證 路由器生成并檢查每個ospf數(shù)據(jù)包。 路由器驗證接收到的每個路由更新數(shù)據(jù)包的來源。 配置“密鑰”（口令）：每個參與的鄰居都必須配置相同的密鑰。it education & trainingdate: 24 october 2021配置ospf身份驗證步驟一：設(shè)

31、定驗證的口令 1、設(shè)定明文口令 router（config-if）# ip ospf authentication-key password 分配用于鄰居路由器的口令（最長8個字符） 2、設(shè)定md5加密的口令 router（config-if）# ip ospf message-digest-key id md5 password 分配用于鄰居路由器的口令（md5加密，最長16個字符）it education & trainingdate: 24 october 2021配置ospf身份驗證步驟二：啟用ospf身份驗證并指定驗證類型 方法1：在接口上直接指定（12.0版本以上提供） r

32、outer（config-if）# ip ospf authentication message-digest | null 指定接口的身份驗證類型 message-digest ：md5加密口令 null ：空口令 方法2：整個ospf 區(qū)域指定驗證類型 router（config-router）# area area-id authentication message-digest message-digest ：md5加密口令it education & trainingdate: 24 october 2021使用ospf配置負載均衡ospf負載均衡 路徑必須為等價路徑 默認情

33、況下，最多可在路由表中加入4條等價路徑 通過更改配置，最多可以配置16條等價路徑 -（config-router）# maximum-paths 可更改鏈路的開銷以確保路徑等價進行負載均衡 -（config-if）# ip ospf cost it education & trainingdate: 24 october 2021修改鏈路成本router#router#config terminalrouter(config)#interface f0/0router(config-if)#ip ospf cost number/number為為1到到65535之間的值之間的值it e

34、ducation & trainingdate: 24 october 2021internet互聯(lián)網(wǎng)局域網(wǎng)：內(nèi)部使用ospf接入互聯(lián)網(wǎng)使用默認路由內(nèi)部計算機如何使用默認路由？默認路由it education & trainingdate: 24 october 2021默認路由發(fā)布到ospf區(qū)域 將默認路由發(fā)布到ospf區(qū)域中，使用以下命令： router（config-router）# default-information originateit education & trainingdate: 24 october 2021課堂作業(yè)e0e0s0s0it education & trainingdate: 24 october 2021思考題（questions）1. ospf是一種典型的_路由協(xié)議。2. ospf路由協(xié)議的管理距離是_。3. ospf路由協(xié)議采用_作為度量標準。4. ospf路由器利用_算法，獨立地計算出到達任意目的地的路由。5. 默認情況下，快速以太網(wǎng)的開銷是_。6. ospf將網(wǎng)絡(luò)劃分為四種類型：_、_、_、_。7. ethernet的hello interval為_秒，dead interval為_秒。8. nbma網(wǎng)絡(luò)的hello interval_秒，dead interva