文档CCNA资料CCNA第5天

第5天一、复习内容：1、管理距离(从不同种路由协议学习到同一个目地的路由)路由来源管理距离直接出口0使用出接口配置的路由0使用下一跳地址配置的静态路由1EIGRP汇总路由5外部BGP20内部EIGRP90IGRP100OSPF110IS-IS自治系统115RIP120EGP外部网关协议140ODR160外部EIGRP170内部BGP2002、Metric(度量值)相同路由协议到目的地有多条路径的时候，选择度量值小的路由(相同的路由协议学习到的路由比较)RIP的metric：跳数(hop)OSPF的metric：COST(=10的8次方/带宽)EIGRP的metric：bandwidth(带宽)+delay(延时)默认情况3、降低RIP路由协议环路的方法：1)水平分割(接口下的命令)默认开启Router(config-if)#no ip split-horizon*从一个接口上学习到的路由信息，不再从这个接口发送出去。2)触发更新RIP环境中一旦有某一链路发生变化，立即向外发送路由更新。3)毒性逆转毒性逆转则是将这样的路由信息METRIC置为无穷大，大于或等于16再发送回去。 RIPv2使用组播地址224.0.0.9发送路由更新。IGRP(Interior Gateway Routing Protocol，内部网关路由协议)二、OSPF协议1)基本IP配置并测试连通性略2)OSPF路由协议配置R1(config)#router ospf 110R1(config-router)#network 1.1.1.0 0.0.0.255 area 0R1(config-router)#network 12.1.1.0 0.0.0.255 area 0R2(config)#router ospf 110R2(config-router)#network 2.2.2.0 0.0.0.255 area 0R2(config-router)#network 12.1.1.0 0.0.0.255 area 0R2(config-router)#network 23.1.1.0 0.0.0.255 area 0R1(config)#router ospf 110R1(config-router)#network 3.3.3.0 0.0.0.255 area 0R1(config-router)#network 23.1.1.0 0.0.0.255 area 03)检查生成的路由表信息并测试到目的网段的连通性R1#show ip routeCodes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter areaN1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGPi - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area* - candidate default, U - per-user static route, o - ODRP - periodic downloaded static routeGateway of last resort is not set1.0.0.0/24 is subnetted, 1 subnetsC 1.1.1.0 is directly connected, Loopback02.0.0.0/32 is subnetted, 1 subnetsO 2.2.2.2 110/2 via 12.1.1.2, 00:03:03, FastEthernet0/03.0.0.0/32 is subnetted, 1 subnetsO 3.3.3.3 110/3 via 12.1.1.2, 00:04:17, FastEthernet0/012.0.0.0/24 is subnetted, 1 subnetsC 12.1.1.0 is directly connected, FastEthernet0/023.0.0.0/24 is subnetted, 1 subnetsO 23.1.1.0 110/2 via 12.1.1.2, 00:07:44, FastEthernet0/0R#ping 3.3.3.3R1#ping 3.3.3.3Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:!Success rate is 100 percent (5/5), round-trip min/avg/max = 0/0/0 msOSPF原理OSPF路由器(邻居)之间交换LSA(Link State Acknowlege)链路状态通告。*OSPF三张表(会用命令)1)邻居表Router#show ip ospf neighbor/邻居的形成，通过hello包，每个OSPF路由器定期向外发送hello包，hello包的作用，用来建立和维护邻居关系。2)拓扑表(链路状态数据库LSDB)由LSA组成的R1#show ip ospf database OSPF Router with ID (1.1.1.1) (Process ID 110)Router Link States (Area 0)Link ID ADV Router Age Seq# Checksum Link count1.1.1.1 1.1.1.1 1218 0x80000003 0x00c354 23.3.3.3 3.3.3.3 913 0x80000005 0x008b59 22.2.2.2 2.2.2.2 840 0x80000005 0x002e94 3Net Link States (Area 0)Link ID ADV Router Age Seq# Checksum12.1.1.1 1.1.1.1 1218 0x80000001 0x00885d23.1.1.2 2.2.2.2 1117 0x80000001 0x00efc13)路由表路由器对本地的LSA通过SPF算法计算出到达目的地的最短路径，之后放在路由表中，进而形成路由表。Router#show ip route ospfR1#show ip route ospf2.0.0.0/32 is subnetted, 1 subnetsO 2.2.2.2 110/2 via 12.1.1.2, 00:18:23, FastEthernet0/03.0.0.0/32 is subnetted, 1 subnetsO 3.3.3.3 110/3 via 12.1.1.2, 00:19:38, FastEthernet0/023.0.0.0/24 is subnetted, 1 subnetsO 23.1.1.0 110/2 via 12.1.1.2, 00:23:05, FastEthernet0/0OSPF使用分层的架构：包括area 0（骨干区域）和非骨干区域，非骨干区域必须和骨干区域区域0相连。*OSPF邻接建立过程0)down1)init2)2-way3)ExStart预启动，交换DBD信息的前奏4)Exchange互相发送LSA的摘要信息(DBD-database description)5)Loading6)full互相学习到对方的所有LSA信息，收敛完成。*查看接口的OSPF信息R1(config)#do show ip ospf inter f0/0FastEthernet0/0 is up, line protocol is upInternet address is 12.1.1.1/24, Area 0Process ID 110, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1Transmit Delay is 1 sec, State BDR, Priority 1Designated Router (ID) 2.2.2.2, Interface address 12.1.1.2Backup Designated Router (ID) 1.1.1.1, Interface address 12.1.1.1Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5Hello due in 00:00:04Index 2/2, flood queue length 0Next 0x0(0)/0x0(0)Last flood scan length is 1, maximum is 1Last flood scan time is 0 msec, maximum is 0 msecNeighbor Count is 1, Adjacent neighbor count is 1Adjacent with neighbor 2.2.2.2 (Designated Router)Suppress hello for 0 neighbor(s)*修改OSPF接口下的hello间隔和死亡间隔R1(config)#inter f0/0R1(config-if)#ip ospf ?authentication Enable authenticationauthentication-key Authentication password (key)cost Interface costdead-interval Interval after which a neighbor is declared deadhello-interval Time between HELLO packetsmessage-digest-key Message digest authentication password (key)priority Router priority*OSPF使用组播地址进行相关信息的交互224.0.0.5(DRothers)和224.0.0.6(DR和BDR)*R1(config)#inter f0/0R1(config-if)#ip ospf priority ? PriorityR1(config-if)#ip ospf priority 2修改接口优先级影响DR和BDR的选举*OSPF的包类型Hello用于邻居路由器之间建立和维护邻接关系数据库描述包DBD描述每台OSPF路由器的链路状态数据库的内容链路状态请求包LSR请求链路状态数据库的部分内容链路状态更新包LSU传送链路状态数据通告LSA给邻居路由器 链路状态确认包LSAck确认邻居发过来的LSA已经收到*OSPF的metric值叫做cost，=10的8次方除以带宽，到目的网络的COST等于链路出向接口(入向接口)链路COST之和。三、EIGRP路由协议Cisco私有的路由私有，高级距离矢量路由协议。EIGRP路由算法DUAL(diffuse update algorithm)扩散更新算法1)EIGRP的三张表1.邻居表R1#show ip eigrp neighborIP-EIGRP neighbors for process 90H Address Interface Hold Uptime SRTT RTO Q Seq(sec) (ms) Cnt Num0 12.1.1.2 Fa0/0 11 00:05:10 40 1000 0 111 14.1.1.4 Fa0/1 12 00:03:13 40 1000 0 222.拓扑表R1#show ip eigrp topologyIP-EIGRP Topology Table for AS 90Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,r - Reply statusP 1.1.1.0/24, 1 successors, FD is 128256via Connected, Loopback0P 3.3.3.0/24, 1 successors, FD is 158720via 12.1.1.2 (158720/156160), FastEthernet0/0P 12.1.1.0/24, 1 successors, FD is 28160via Connected, FastEthernet0/0P 14.1.1.0/24, 1 successors, FD is 28160via Connected, FastEthernet0/1P 23.1.1.0/24, 1 successors, FD is 30720via 12.1.1.2 (30720/28160), FastEthernet0/0P 34.1.1.0/24, 1 successors, FD is 2172416via 14.1.1.4 (2172416/2169856), FastEthernet0/13.路由表R1#show ip route eigrp3.0.0.0/24 is subnetted, 1 subnetsD 3.3.3.0 90/158720 via 12.1.1.2, 00:05:10, FastEthernet0/023.0.0.0/24 is subnetted, 1 subnetsD 23.1.1.0 90/30720 via 12.1.1.2, 00:06:04, FastEthernet0/034.0.0.0/24 is subnetted, 1 subnetsD 34.1.1.0 90/2172416 via 14.1.1.4, 00:04:27, FastEthernet0/1*EIGRP实验1)实验拓扑2)基本IP配置并测试连通性R1(config)#inter lo0R1(config-if)#ip add 1.1.1.1 255.255.255.0R1(config-if)#inter f0/0R1(config-if)#ip add 12.1.1.1 255.255.255.0R1(config-if)#no shutR1(config-if)#inter f0/1R1(config-if)#ip add 14.1.1.1 255.255.255.0R1(config-if)#no shutR2(config)#inter f0/1R2(config-if)#ip add 12.1.1.2 255.255.255.0R2(config-if)#no shutR2(config-if)#inter f0/0R2(config-if)#ip add 23.1.1.2 255.255.255.0R2(config-if)#no shutR3(config)#inter lo0R3(config-if)#ip add 3.3.3.3 255.255.255.0R3(config-if)#no shutR3(config-if)#inter f0/1R3(config-if)#ip add 23.1.1.3 255.255.255.0R3(config-if)#no shutR3(config-if)#inter s0/0/1R3(config-if)#ip add 34.1.1.3 255.255.255.0R3(config-if)#no shutR4(config)#inter f0/0R4(config-if)#ip add 14.1.1.4 255.255.255.0R4(config-if)#no shutR4(config-if)#inter s0/0/0R4(config-if)#ip add 34.1.1.4 255.255.255.0R4(config-if)#no shut3)EIGRP路由协议配置R1(config)#router eigrp 90R1(config-router)#no auto-summary R1(config-router)#network 1.1.1.0 ?R1(config-router)#network 1.1.1.0 0.0.0.255R1(config-router)#network 12.1.1.0 0.0.0.255R1(config-router)#network 14.1.1.0 0.0.0.255R2(config)#router eigrp 90R2(config-router)#no autoR2(config-router)#network 12.1.1.0 0.0.0.255R2(config-router)#network 23.1.1.0 0.0.0.255R3(config)#router eigrp 90R3(config-router)#no auto-summary R3(config-router)#network 3.3.3.0 0.0.0.255 R3(config-router)#network 23.1.1.0 0.0.0.255R3(config-router)#network 34.1.1.0 0.0.0.255R4(config)#router eigrp 90R4(config-router)#no autoR4(config-router)#network 34.1.1.0 0.0.0.255R4(config-router)#network 14.1.1.0 0.0.0.2553)验证路由条目前测试是否全网可达R1#show ip routeCodes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF