实验52: 帧中继环境下NBMA 模式
1.
实验目的
通过本实验可以掌握:
(1)帧中继静态映射及broadcast 参数的含义
(2)NBMA 模式下的DR 选举
(3)手工配置OSPF 邻居
(4)NBMA 模式下OSPF 的配置和调试
2.
拓扑结构
实验拓扑
3.
实验步骤
注:
1.
帧中继是典型的
NBMA
(NonBroadcast Multiple Access)网络,其拓扑结构通常有
两种:
Full Mesh(
全互联
)
和Hub-and-Spoke(中心-分支)。
2.
在帧中继网络上,OSPF 接口缺省的网络类型为NON_BROADCAST。在这种模式下,
OSPF
不会在帧中继接口上发送Hello 包,因此无法建立最基本的邻接关系。可以手工使用
“neighbor”命令来指定邻居,这时Hello 包以单播形式传送;
3.NBMA
属于多路访问网络,所以要进行DR 选举。
r1(config)#int loo 1
*Mar 1 00:00:53.591: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback1, changed state to up
r1(config-if)#ip add 1.1.1 .1 255.255.255.0
r1(config-if)#int s0/0
r1(config-if)#ip add 172.16.1.1 255.255.255.0
r1(config-if)#no sh
r1(config-if)#exit
r1(config)#int loo 1
r1(config-if)#ip ospf net point-to-point
r1(config-if)#no sh
r1(config-if)#exit
r1(config)#int s0/0
r1(config-if)#enca frame-relay
r1(config-if)#
*Mar 1 00:02:32.363: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to up
r1(config-if)#frame-relay map ip 172.16.1.1 101 broadcast
//
帧中继静态映射
r1(config-if)#no frame-relay map ip 172.16.1.1 101 broadcast
r1(config-if)#frame-relay map ip 172.16.1.2 101 broadcast
r1(config-if)#frame-relay map ip 172.16.1.3 101 broadcast
r1(config-if)#frame-relay map ip 172.16.1.1 101
//
使得可以PING 通自己
r1(config-if)#no fram inver
//
关闭帧中继动态ARP 解析
r1(config-if)#no sh
r1(config-if)#exit
r1(config)#router ospf 1
r1(config-router)#net 1.1.1 .0 0.0.0.255 area 0
r1(config-router)#net 172.16.1.0 0.0.0 .255 area 0
r1(config-router)#nei 172.16.1.2
//
手工指OSPF 邻居
r1(config-router)#nei 172.16.1.3
r1(config-router)#
*Mar 1 00:12:38.303: %OSPF-5-ADJCHG: Process 1, Nbr 3.3.3 .3 on Serial0/0 from LOADING to FULL, Loading Done
r1(config-router)#do ping 172.16.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 24/52/84 ms
r1(config-router)#do ping 172.16.1.
*Mar 1 00:13:34.895: %OSPF-5-ADJCHG: Process 1, Nbr 2.2.2 .2 on Serial0/0 from LOADING to FULL, Loading Done
r1(config-router)#do ping 172.16.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/55/96 ms
r1(config-router)#do sh 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
C 1.1.1 .0 is directly connected, Loopback1
2.0.0 .0/24 is subnetted, 1 subnets
O 2.2.2 .0 [110/65] via 172.16.1.2, 00:00:04, Serial0/0
3.0.0 .0/24 is subnetted, 1 subnets
O 3.3.3 .0 [110/65] via 172.16.1.3, 00:00:04, Serial0/0
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/0
r1(config-router)#do sh ip ospf int
Serial0/0 is up, line protocol is up
Internet Address 172.16.1.1/24, Area 0
Process ID 1, Router ID 1.1.1 .1, Network Type NON_BROADCAST, Cost: 64
//
接口网络类型为NBMA 模式
Transmit Delay is 1 sec, State BDR, Priority 1
//
自己是DR,接口优先级为1
Designated Router (ID) 3.3.3 .3, Interface address 172.16.1.3
//DR
的ID 和接口地址
Backup Designated router (ID) 1.1.1 .1, Interface address 172.16.1.1
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
//NBMA
模式下,Hello 周期为30 秒
oob-resync timeout 120
Hello due in 00:00:27
Supports Link-local Signaling (LLS)
Index 2/2, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 2, Adjacent neighbor count is 2
Adjacent with neighbor 2.2.2 .2
Adjacent with neighbor 3.3.3 .3 (Designated Router)
//
与路由器R2 和R3 形成邻接关系
Suppress hello for 0 neighbor(s)
Loopback1 is up, line protocol is up
Internet Address 1.1.1 .1/24, Area 0
Process ID 1, Router ID 1.1.1 .1, Network Type POINT_TO_POINT, Cost: 1
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
oob-resync timeout 40
Supports Link-local Signaling (LLS)
Index 1/1, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
r1(config-router)#
r2(config)#int loo 1
r2(config-if)#ip add 2.
*Mar 1 00:03:58.971: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback1, changed state to up
r2(config-if)#ip add 2.2.2 .2 255.255.255.0
r2(config-if)#ip ospf net point-to-point
r2(config-if)#no sh
r2(config-if)#int s0/0
r2(config-if)#ip add 172.16.1.2 255.255.255.0
r2(config-if)#no sh
r2(config-if)#
*Mar 1 00:05:04.619: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to down
r2(config-if)#enca fram
r2(config-if)#
*Mar 1 00:11:13.395: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to up
r2(config-if)#frame map ip 172.16.1.1 201 broadcast
r2(config-if)#frame map ip 172.16.1.3 201 broadcast
r2(config-if)#frame map ip 172.16.1.2 201
r2(config-if)#no fram inver
r2(config-if)#no sh
r2(config-if)#exit
r2(config)#router ospf 1
r2(config-router)#router-id 2.2.2 .2
r2(config-router)#net 2.2.2 .0 0.0.0.255 area 0
r2(config-router)#net 172.16.1.0 0.0.0 .255 area 0
r2(config-router)#nei 172.16.1.1
r2(config-router)#nei 172.16.1.3
r2(config-router)#
*Mar 1 00:13:35.571: %OSPF-5-ADJCHG: Process 1, Nbr 1.1.1 .1 on Serial0/0 from LOADING to FULL, Loading Done
*Mar 1 00:15:16.707: %OSPF-5-ADJCHG: Process 1, Nbr 0.0.0 .0 on Serial0/0 from ATTEMPT to DOWN, Neighbor Down: Dead timer expired
r2(config-router)#
r3(config)#int loo 1
r3(config-if)#ip add
*Mar 1 00:04:49.783: %LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback1, changed state to up 172.16.1.3 255.255.255.0
r3(config-if)#no sh
r3(config-if)#no ip add
r3(config-if)#ip add 3.3.3 .3 255.255.255.0
r3(config-if)#ip ospf net point-to-point
r3(config-if)#no sh
r3(config-if)#exit
r3(config)#int s0/0
r3(config-if)#ip add 172.16.1.3 255.255.255.0
r3(config-if)#no sh
r3(config-if)#
*Mar 1 00:06:16.483: %LINK-3-UPDOWN: Interface Serial0/0, changed state to upenc
*Mar 1 00:06:17.487: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to upap
% Incomplete command.
r3(config-if)#encap fram
r3(config-if)#frame-relay map ip 172.16.1.1 302
r3(config-if)#frame-relay map ip 172.16.1.1 302 broadcast
r3(config-if)#frame-relay map ip 172.16.1.2 302 broadcast
r3(config-if)#frame-relay map ip 172.16.1.3
*Mar 1 00:07:09.467: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to down302
r3(config-if)#no fr
*Mar 1 00:07:29.467: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0, changed state to upam inver
r3(config-if)#no sh
r3(config-if)#exit
r3(config)#router ospf 1
r3(config-router)#router-id 1.1.1 .1
r3(config-router)#no router-id 1.1.1 .1
r3(config-router)#router-id 3.3.3 .3
r3(config-router)#net 3.3.3 .0 0.0.0.255 area 0
r3(config-router)#net 172.16.1.0 0.0.0 .255 area 0
r3(config-router)#neighbor 172.16.1.1
r3(config-router)#neigh 172.16.1.2
r3(config-router)#
*Mar 1 00:12:38.731: %OSPF-5-ADJCHG: Process 1, Nbr 0.0.0 .0 on Serial0/0 from ATTEMPT to DOWN, Neighbor Down: Dead timer expired
*Mar 1 00:12:38.959: %OSPF-5-ADJCHG: Process 1, Nbr 1.1.1 .1 on Serial0/0 from LOADING to FULL, Loading Done
r3(config-router)#do sh 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
O 1.1.1 .0 [110/65] via 172.16.1.1, 00:01:21, Serial0/0
3.0.0 .0/24 is subnetted, 1 subnets
C 3.3.3 .0 is directly connected, Loopback1
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/0
r3(config-router)#
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