Cisco(思科)路由器静态路由的配置

实验拓扑

实验步骤

我们要使得 1.1.1.0/24、2.2.2.0/24、3.3.3.0/24 网络之间能够互相通信。

(1)  步骤 1:在各路由器上配置 IP 地址、保证直连链路的连通性

R1(config)#int loopback0

R1(config-if)#ip address 1.1.1.1 255.255.255.0

R1(config)#int s0/0/0

R1(config-if)#ip address 192.168.12.1 255.255.255.0

R1(config-if)#no shutdown

R2(config)#int loopback0

R2(config-if)#ip address 2.2.2.2 255.255.255.0

R2(config)#int s0/0/0

R2(config-if)#clock rate 128000

R2(config-if)#ip address 192.168.12.2 255.255.255.0

R2(config-if)#no shutdown

R2(config)#int s0/0/1

R2(config-if)#clock rate 128000

R2(config-if)#ip address 192.168.23.2 255.255.255.0

R2(config-if)#no shutdown

R3(config)#int loopback0

R3(config-if)#ip address 3.3.3.3 255.255.255.0

R3(config)#int s0/0/1

R3(config-if)#ip address 192.168.23.3 255.255.255.0

R3(config-if)#no shutdown

(2)  步骤 2:R1上配置静态路由

R1(config)#ip route 2.2.2.0 255.255.255.0 s0/0/0

//下一跳为接口形式,s0/0/0 是点对点的链路,注意应该是 R1 上的s0/0/0 接口

R1(config)#ip route 3.3.3.0 255.255.255.0 192.168.12.2

//下一跳为IP 地址形式,192.168.12.2 是R2 上的IP 地址

(3)  步骤 3:R2上配置静态路由

R2(config)#ip route 1.1.1.0 255.255.255.0 s0/0/0

R2(config)#ip route 3.3.3.0 255.255.255.0 s0/0/1

(4)  步骤 4:R3上配置静态路由

R3(config)#ip route 1.1.1.0 255.255.255.0 s0/0/1

R3(config)#ip route 2.2.2.0 255.255.255.0 s0/0/1

实验调试
(1) 在 R1、R2、R3 上查看路由表

R1#show ip route
Codes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.12.0/24 is directly connected, Serial0/0/0
1.0.0.0/24 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, Loopback0
2.0.0.0/24 is subnetted, 1 subnets
S 2.2.2.0 is directly connected, Serial0/0/0
3.0.0.0/24 is subnetted, 1 subnets
S 3.3.3.0 [1/0] via 192.168.12.2

R2#show ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.12.0/24 is directly connected, Serial0/0/0
1.0.0.0/24 is subnetted, 1 subnets
S 1.1.1.0 is directly connected, Serial0/0/0

2.0.0.0/24 is subnetted, 1 subnets
C 2.2.2.0 is directly connected, Loopback0
3.0.0.0/24 is subnetted, 1 subnets
S 3.3.3.0 is directly connected, Serial0/0/1

C 192.168.23.0/24 is directly connected, Serial0/0/1

R3#show ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
1.0.0.0/24 is subnetted, 1 subnets
S 1.1.1.0 is directly connected, Serial0/0/1

2.0.0.0/24 is subnetted, 1 subnets
S 2.2.2.0 is directly connected, Serial0/0/1

3.0.0.0/24 is subnetted, 1 subnets C 3.3.3.0 is directly connected, Loopback0
C 192.168.23.0/24 is directly connected, Serial0/0/1

(2) 从各路由器的环回口 ping 其他路由器的环回口:

R1#ping
//不带任何参数的 ping命令,允许我们输入更多的参数
Protocol [ip]:
Target IP address: 2.2.2.2 //目标IP地址
Repeat count [5]: //发送的ping 次数
Datagram size [100]: //ping包的大小
Timeout in seconds [2]: //超时时间
Extended commands [n]: y //是否进一步扩展命令
Source address or interface: 1.1.1.1 //源IP地址
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 1.1.1.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms

//以上说明从 R1 的 loopback0 可以ping 通R2 上的 loopback0。也可以直接使用命令:
R1#ping 2.2.2.2 source loopback 0
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 1.1.1.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms

R2#ping 1.1.1.1 source loopback 0
R2#ping 3.3.3.3 source loopback 0
//从R2 的 loopback0 应该可以 ping 通R1 和 R3 的lopback0 接口。

R3#ping 1.1.1.1 source loopback 0
R3#ping 2.2.2.2 source loopback 0
//从R3 的 loopback0 也应该可以 ping 通 R1 和 R2 的 lopback0 接口。
【提示】虽然从 R1 的 loopback0 可以 ping 通 R3 的 loopback0,数据需要经过192.168.23.0/24 网络,但是在 R1 上我们并没有添加192.168.23.0/24 的路由。路由器转发数据包完成是根据路由表的,并且数据是一跳一跳地被转发的,就像接力赛似的。从 R1的loopback0口ping R3的loopback0口时, IP数据包的源IP为1.1.1.1, 目的IP为3.3.3.3。
R1 路由器首先查路由表,数据包被发到了 R2;R2 路由器也查路由表(3.3.3.0/24 路由) ,数据包被发到了 R3;R3知道这是直连路由。R3响应 R1 的数据包进行类似的过程。
(3) 从 R1 上 ping 2.2.2.2、从 R1 上 ping 3.3.3.3
R1#ping 2.2.2.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/14/16 ms
//可以ping通。
R1#ping 3.3.3.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
//以上无法ping通, 原因在于使用ping命令时, 如果不指明源接口, 则R1路由器使用s0/0/0接口的 IP 地址(192.168.12.1)作为 IP 数据包的源 IP 地址了。R3 上响应R1 的数据包时,数据包是发向 192.168.12.1 的,然而由于 R3 没有192.168.12.0/24 的路由,数据包无法发送。即:数据包从 R1 到了 R3 后,无法返回 R1。

posted @ 2014-03-23 23:38  云龙  阅读(6176)  评论(1编辑  收藏  举报