FR上的OSPF之一：NBMA模式
实验拓扑图
实验目的
调试在帧中继环境下的OSPF配置，NBMA网络模式
实验配置
(一) 配置IP地址
(二) 运行OSPF并通告网络
(三) 查看R1的邻居以及接口状态
通过查看，发现三台路由器并没有建立邻居关系
每台路由器都把自己视为多路访问链路的DR
R1#show ip ospf neighbor
R1#show ip ospf interface
Loopback0 is up, line protocol is up
Internet Address 1.1.1.1/24, Area 0
Process ID 110, 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 2/2, 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)
Serial0/0 is up, line protocol is up
Internet Address 123.1.1.1/24, Area 0
Process ID 110, Router ID 1.1.1.1, Network Type NON_BROADCAST, Cost: 64
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router (ID) 1.1.1.1, Interface address 123.1.1.1
No backup designated router on this network
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
oob-resync timeout 120
Hello due in 00:00:05
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)
(四) 解决办法
1. 配置命令
R1的配置
interface Serial0/0
ip address 123.1.1.1 255.255.255.0
encapsulation frame-relay
serial restart-delay 0
no dce-terminal-timing-enable
frame-relay map ip 123.1.1.3 103 broadcast
frame-relay map ip 123.1.1.1 102
frame-relay map ip 123.1.1.2 102 broadcast
router ospf 110
router-id 1.1.1.1
log-adjacency-changes
network 1.1.1.0 0.0.0.255 area 0
network 123.1.1.0 0.0.0.255 area 0
neighbor 123.1.1.2
neighbor 123.1.1.3
R2的配置
interface Serial0/0
ip address 123.1.1.2 255.255.255.0
encapsulation frame-relay
ip ospf priority 0
serial restart-delay 0
no dce-terminal-timing-enable
frame-relay map ip 123.1.1.3 201 broadcast
frame-relay map ip 123.1.1.1 201 broadcast
frame-relay map ip 123.1.1.2 201
router ospf 110
router-id 2.2.2.2
log-adjacency-changes
network 2.2.2.0 0.0.0.255 area 0
network 123.1.1.0 0.0.0.255 area 0
R3的配置
interface Serial0/0
ip address 123.1.1.3 255.255.255.0
encapsulation frame-relay
ip ospf priority 0
serial restart-delay 0
no dce-terminal-timing-enable
frame-relay map ip 123.1.1.3 301
frame-relay map ip 123.1.1.1 301 broadcast
frame-relay map ip 123.1.1.2 301 broadcast
no frame-relay inverse-arp
router ospf 110
router-id 3.3.3.3
log-adjacency-changes
network 3.3.3.0 0.0.0.255 area 0
network 123.1.1.0 0.0.0.255 area 0
!
总结：
1. 在中心路由器上指定两个分支为邻居
2. 使用frame-relay map来广播DLCI
3. 在分支之间也要使用frame-relay map来广播DLCI
4. 在分支路由器上指定连接NBMA网络的接口优先级为0
5. 检查帧中继map 是否为active
6. 分支路由器之间的通信通过中心路由器来中转
7. Hello包为单播包，每30秒发送一次
R3# show frame-relay map
Serial0/0 (up): ip 123.1.1.3 dlci 301(0x12D,0x48D0), static,
CISCO, status defined, active
Serial0/0 (up): ip 123.1.1.1 dlci 301(0x12D,0x48D0), static,
broadcast,
CISCO, status defined, active
Serial0/0 (up): ip 123.1.1.2 dlci 301(0x12D,0x48D0), static,
broadcast,
CISCO, status defined, active
R3#traceroute 2.2.2.2
Type escape sequence to abort.
Tracing the route to 2.2.2.2
1 123.1.1.1 144 msec 76 msec 80 msec
2 123.1.1.2 140 msec * 236 msec
R3#
*Mar 1 00:57:14.211: OSPF: Send hello to 123.1.1.1 area 0 on Serial0/0 from 123.1.1.3
R3#
*Mar 1 00:57:16.819: OSPF: Rcv hello from 1.1.1.1 area 0 from Serial0/0 123.1.1.1
*Mar 1 00:57:16.819: OSPF: End of hello processing
R3#
*Mar 1 00:57:44.211: OSPF: Send hello to 123.1.1.1 area 0 on Serial0/0 from 123.1.1.3
R3#
*Mar 1 00:57:46.887: OSPF: Rcv hello from 1.1.1.1 area 0 from Serial0/0 123.1.1.1
*Mar 1 00:57:46.891: OSPF: End of hello processing
R3#
转载于:https://blog.51cto.com/liu008qing/455639