【正文】 B C E0 S0 S0 S1 S0 E0 X Routing Table S0 S0 S0 S0 1 2 0 2 Routing Table E0 S0 S0 S0 1 4 0 0 Routing Table S0 S1 S1 S0 3 1 0 0 169。 1999, Cisco Systems, Inc. ICND—928 無 限 計 數(shù) ? 網(wǎng)絡(luò)的數(shù)據(jù)將在路由器 A, B, 和 C 之間循環(huán) ? 網(wǎng)絡(luò)的跳數(shù)將無限大 A B C E0 S0 S0 S1 S0 E0 X Routing Table S0 S0 S0 S0 1 2 0 4 Routing Table E0 S0 S0 S0 1 6 0 0 Routing Table S0 S1 S1 S0 5 1 0 0 169。 1999, Cisco Systems, Inc. ICND—929 解決方法：定義最大跳數(shù) 指定最大跳數(shù)來防止路由回環(huán) A B C E0 S0 S0 S1 S0 E0 X Routing Table S0 S0 S0 S0 1 2 0 16 Routing Table E0 S0 S0 S0 1 16 0 0 Routing Table S0 S1 S1 S0 16 1 0 0 169。 1999, Cisco Systems, Inc. ICND—930 解決方法：水平分割 不會接收到由自身傳達(dá)出去的路由信息 A B C E0 S0 S0 S1 S0 E0 X X X Routing Table S0 S0 S0 S0 1 2 0 0 Routing Table E0 S0 S0 S0 1 2 0 0 Routing Table S0 S1 S1 E1 1 2 0 0 169。 1999, Cisco Systems, Inc. ICND—931 解決方法：路由毒殺 路由器將該路由信息的跳數(shù)標(biāo)記為無限大 A B C E0 S0 S0 S1 S0 E0 X Routing Table S0 S0 S0 S0 1 2 0 Infinity Routing Table E0 S0 S0 S0 1 2 0 0 Routing Table S0 S1 S1 E1 1 2 0 0 169。 1999, Cisco Systems, Inc. ICND—932 解決方法：反轉(zhuǎn)毒殺 反轉(zhuǎn)毒殺可以超越水平分割 A B C E0 S0 S0 S1 S0 E0 X Routing Table S0 S0 S0 S0 1 2 0 Infinity Routing Table E0 S0 S0 S0 1 2 0 0 Routing Table S0 S1 S1 E1 Possibly Down 2 0 0 Poison Reverse 169。 1999, Cisco Systems, Inc. ICND—933 解決方法： HoldDown 計時 路由器在 HoldDown時間內(nèi)將該條記錄標(biāo)記為 possibly down以使其它路由器能夠重新計算網(wǎng)絡(luò)結(jié)構(gòu)的變化 Network is down then back up then back down Update after holddown Time Network is unreachable A B C E0 S0 S0 S1 S0 E0 X Update after holddown Time 169。 1999, Cisco Systems, Inc. ICND—934 解決方法：觸發(fā)更新 當(dāng)路由表發(fā)生變化時路由器立即發(fā)送更新信息 A B C E0 S0 S0 S1 S0 E0 X Network is unreachable Network is unreachable Network is unreachable 169。 1999, Cisco Systems, Inc. ICND—935 鏈路狀態(tài)協(xié)議 傳遞最佳的路徑信息給其它的路由器 LSP數(shù)據(jù)包 SPF 運(yùn)算 拓補(bǔ)結(jié)構(gòu)數(shù)據(jù) 最佳路由信息 路由表 C A D B 169。 1999, Cisco Systems, Inc. ICND—936 路由器配置 ? 選擇路由協(xié)議 ? 指定網(wǎng)絡(luò)或端口 Network Network IGRP, RIP Network RIP RIP IGRP IP路由的配置任務(wù) 169。 1999, Cisco Systems, Inc. ICND—937 ? 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(luò) Router(configrouter)work worknumber 動態(tài)路由配置 169。 1999, Cisco Systems, Inc. ICND—938 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 169。 1999, Cisco Systems, Inc. ICND—939 ? 激活 RIP協(xié)議 Router(config)router rip Router(configrouter)work worknumber ? 選擇所能到達(dá)的網(wǎng)絡(luò) ? 必須是有效的網(wǎng)絡(luò) RIP 配 置 169。 1999, Cisco Systems, Inc. ICND—940 router rip work work RIP 配置舉例 router rip work router rip work work S2 E0 S3 S2 S3 A B C E0 169。 1999, Cisco Systems, Inc. ICND—941 查看 RIP信息 RouterAsh ip protocols Routing Protocol is rip Sending updates every 30 seconds, next due in 0 seconds Invalid after 180 seconds, hold down 180, flushed after 240 Outgoing update filter list for all interfaces is Ining update filter list for all interfaces is Redistributing: rip Default version control: send version 1, receive any version Interface Send Recv Keychain Ether0 1 1 2 Serial2 1 1 2 Routing for Networks: Routing Information Sources: Gateway Distance Last Update 120 00:00:10 Distance: (default is 120) S2 E0 S3 S2 S3 A B C E0 169。 1999, Cisco Systems, Inc. ICND—942 查看路由表 RouterAsh ip route Codes: C connected, S 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, E2 OSPF external type 2, E EGP i ISIS, L1 ISIS level1, L2 ISIS level2, * candidate default U peruser static route, o ODR T traffic engineered route Gateway of last resort is not set , 1 subs C is directly connected, Ether0 , 2 subs R [120/1] via , 00:00:07, Serial2 C is directly connected, Serial2 R [120/2] via , 00:00:07, Serial2 S2 E0 S3 S2 S3 A B C E0 169。 1999, Cisco Systems, Inc. ICND—943 debug ip rip 命令 RouterAdebug ip rip RIP protocol debugging is on RouterA 00:06:24: RIP: received v1 update from on Serial2