Router(config)#frame-relay switching把路由器模擬成幀中繼交換機

Router(config)#inter s1/1

Router(config-if)#clock rate 128000

Router(config-if)#encapsulation frame-relay 配置接口封裝幀中繼

接口上啟用的默認(rèn)幀中繼封裝為Cisco封裝，如果連接到非思科路由器，要使用itef參數(shù)

Router(config-if)#no shu

Router(config)#inter s1/2

Router(config-if)#clo rate 128000

Router(config-if)#encapsulation fr

Router(config-if)#no shu

changed state to upnointer s1/3

Router(config-if)#clo rate 128000

Router(config-if)#encapsulation fr

Router(config-if)#no shu

Router(config)#inter s1/1

Router(config-if)#frame-relay lmi-type cisco 配置LMI類型

Router(config-if)#frame-relay intf-type dce 配置接口為幀中繼的DCE

Router(config-if)#inter s1/2

Router(config-if)#frame-relay lmi-type cisco

Router(config-if)#frame-relay intf-type dce

Router(config-if)#inter s1/3

Router(config-if)#frame-relay lmi-type cisco

Router(config-if)#frame-relay intf-type dce

配置路由器兩個接口之間的pvc

Router(config)#inter s1/1

Router(config-if)#frame-relay route 103 inter s1/2 301

Router(config-if)#frame-relay route 104 inter s1/3 401

Router(config-if)#exit

Router(config)#inter s1/2

Router(config-if)#frame-relay route 301 inter s1/1 103

Router(config-if)#frame-relay route 304 inter s1/3 403

Router(config-if)#exit

Router(config)#inter s1/3

Router(config-if)#frame-relay route 401 inter s1/1 104

Router(config-if)#frame-relay route 403 inter s1/2 304

Router(config-if)#

Router#show frame-relay route

Input IntfInput DlciOutput Intf Output Dlci Status

Serial1/1 103 Serial1/2 301 active

Serial1/1 104 Serial1/3 401 active

Serial1/2 301 Serial1/1 103 active

Serial1/2 304 Serial1/3 403 active

Serial1/3 401 Serial1/1 104 active

Serial1/3 403 Serial1/2 304 active

表明路由器R2上配置3條PVC 狀態(tài)都是活動的

R1的配置

Router(config)#inter s1/1

Router(config-if)#ip address 172.16.134.1 255.255.255.0

Router(config-if)#encapsulation fr 接口封裝幀中繼

Router(config-if)#frame-relay lmi-type cisco

Router(config)#inter fa0/0

Router(config-if)#ip add

Router(config-if)#ip address 192.168.1.1 255.255.255.0

Router(config-if)#no shu

如果采用Cisco路由器的IOS是11.2及以后的版本，路由器可以自動協(xié)商LMI是類型

所以可以不配

Router(config)#router rip

Router(config-router)#ver 2

Router(config-router)#no auto-summary

Router(config-router)#network 172.16.134.0

Router(config-router)#network 192.168.1.0

Router(config-router)#exit

R3和R4同R1

ping測試

Router#ping 172.16.134.1 source 192.168.4.1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.16.134.1, timeout is 2 seconds:

Packet sent with a source address of 192.168.4.1

Success rate is 100 percent (5/5), round-trip min/avg/max = 120/155/200 ms

查看幀中繼的映射

 

Router#show frame-relay map

Serial1/1 (up): ip 172.16.134.3 dlci 103(0x67,0x1870), dynamic,

broadcast,, status defined, active

Serial1/1 (up): ip 172.16.134.4 dlci 104(0x68,0x1880), dynamic,

broadcast,, status defined, active

以上輸出顯示了逆向ARP的作用結(jié)果 表明路由器R1每個封裝幀中繼的接口都包含2條處于活動狀態(tài)的DLCI，每條都顯示了遠(yuǎn)程Ip地址與本地的DLCI的映射關(guān)系

broadcast“參數(shù)允許在PVC上傳輸廣播或組播流量 “dynamic 表明動態(tài)映射

每臺路由器都不能ping通自己的串行接口的ip地址，但是可以ping通遠(yuǎn)程封裝幀中繼的串行接口的ip地址 是因為自己的幀中繼映射表中沒有自己的接口ip地址和DLCI的映射條目。 逆向ARP做動態(tài)映射解決不了該問題，只能通過靜態(tài)映射解決

Router#show ip route rip

R192.168.4.0/24 [120/1] via 172.16.134.4, 00:00:07, Serial1/1

R192.168.3.0/24 [120/1] via 172.16.134.3, 00:00:27, Serial1/1

Router#show ip route rip

R192.168.4.0/24 [120/1] via 172.16.134.4, 00:00:00, Serial1/2

R192.168.1.0/24 [120/1] via 172.16.134.1, 00:00:05, Serial1/2

Router#show ip route rip

R192.168.1.0/24 [120/1] via 172.16.134.1, 00:00:18, Serial1/3

R192.168.3.0/24 [120/1] via 172.16.134.3, 00:00:27, Serial1/3

在本實驗中，幀中繼交換機在路由器R2上采用了PVC全互連的拓?fù)浣Y(jié)構(gòu)

但是在實際應(yīng)用中，為了節(jié)省費用，一般采用(中心--分支)的拓?fù)浣Y(jié)構(gòu)

即只有分支到中心的PVC，假如R1是中心路由 R2和R3是分支路由

在R2上是配置如下

Router(config)#inter s1/2

Router(config-if)#no frame-relay route 304 interface s1/3 403

Router(config-if)#inter s1/3

Router(config-if)#no frame-relay route 403 interface s1/2 304

在R3和R4上

Router#show frame-relay map

Serial1/2 (up): ip 172.16.134.1 dlci 301(0x12D,0x48D0), dynamic,

broadcast,, status defined, active

Router#show frame-relay map

Serial1/3 (up): ip 172.16.134.1 dlci 401(0x191,0x6410), dynamic,

broadcast,, status defined, active

可以看到R3和R4上只有一條到中心站點路由器R1的映射

R4和R3的網(wǎng)絡(luò)不可達(dá)

R1

配置幀中繼的靜態(tài)映射

Router(config)#inter s1/1

Router(config-if)#no frame-relay inverse-arp

關(guān)閉逆向ARP ，默認(rèn)是開啟的

Router(config-if)#frame-relay map ip 172.16.134.3 103 broadcast

配置幀中繼靜態(tài)映射

Router(config-if)#frame-relay map ip 172.16.134.4 104 broadcast

Router(config-if)#frame-relay map ip 172.16.134.1 104 broadcast

配置自己接口的ip地址的映射，目的是允許ping路由器該接口的ip地址

R3

Router(config)#inter s1/2

Router(config-if)#no frame-relay inverse-arp

Router(config-if)#frame-relay map ip 172.16.134.1 301 broadcast

Router(config-if)#frame-relay map ip 172.16.134.4 304 broadcast

Router(config-if)#frame-relay map ip 172.16.134.3 301 broadcast

R4

Router(config)#inter s1/3

Router(config-if)#no frame-relay inverse-arp

Router(config-if)#frame-relay map ip 172.16.134.1 401 broadcast

Router(config-if)#frame-relay map ip 172.16.134.3 403 broadcast

Router(config-if)#frame-relay map ip 172.16.134.4 401 broadcast

R1#show frame-relay map

Serial1/1 (up): ip 172.16.134.1 dlci 104(0x68,0x1880), static,

broadcast,

CISCO, status defined, active

Serial1/1 (up): ip 172.16.134.3 dlci 103(0x67,0x1870), static,

broadcast,

CISCO, status defined, active

Serial1/1 (up): ip 172.16.134.4 dlci 104(0x68,0x1880), static,

broadcast,

CISCO, status defined, active

R3#show frame-relay map

Serial1/2 (up): ip 172.16.134.1 dlci 301(0x12D,0x48D0), static,

broadcast,

CISCO, status defined, active

Serial1/2 (up): ip 172.16.134.3 dlci 301(0x12D,0x48D0), static,

broadcast,

CISCO, status defined, active

Serial1/2 (up): ip 172.16.134.4 dlci 301(0x12D,0x48D0), static,

broadcast,

CISCO, status defined, active

R4#show frame-relay map

Serial1/3 (up): ip 172.16.134.1 dlci 401(0x191,0x6410), static,

broadcast,

CISCO, status defined, active

Serial1/3 (up): ip 172.16.134.3 dlci 401(0x191,0x6410), static,

broadcast,

CISCO, status defined, active

Serial1/3 (up): ip 172.16.134.4 dlci 401(0x191,0x6410), static,

broadcast,

CISCO, status defined, active

封裝幀中繼每個接口都采用了靜態(tài)映射

R1#show ip route rip

R192.168.4.0/24 [120/1] via 172.16.134.4, 00:00:26, Serial1/1

R192.168.3.0/24 [120/1] via 172.16.134.3, 00:00:07, Serial1/1

R1#show ip interface s1/1

Serial1/1 is up, line protocol is up

Internet address is 172.16.134.1/24

Broadcast address is 255.255.255.255

Split horizon is disabled接口封裝幀中繼后，水平分割被自動關(guān)閉

R1(R1(config)#inter s1/1

R1(config-if)#ip split-horizon 開啟水平分割

R1#clear ip route * 清除路由表

R1#show ip route rip

R192.168.4.0/24 [120/1] via 172.16.134.4, 00:00:07, Serial1/1

R192.168.3.0/24 [120/1] via 172.16.134.3, 00:00:11, Serial1/1

重新獲得

R3#show ip route rip

R192.168.1.0/24 [120/1] via 172.16.134.1, 00:00:15, Serial1/2

R4#show ip route rip

R192.168.1.0/24 [120/1] via 172.16.134.1, 00:00:06, Serial1/3

R3沒有了R4的路由

R4沒有了R3的路由