NBMA实验
实验准备:
1、 四台路由器,R2配置成帧中继交换机。
2、 R1,R3,R4运行OSPF。
实验配置:
R1:
interface Loopback0
 ip address 1.1.1.1 255.255.255.0
 ip ospf network point-to-point            使路由正常。
interface Serial0/0
 ip address 134.1.1.1 255.255.255.0
 encapsulation frame-relay                封装成帧中继。
 ip ospf network non-broadcast            配置成NBMA的网络。
 ip ospf priority 255                     使R1成为DR。接口悠闲级。
frame-relay map ip 134.1.1.3 103 broadcast   用广播方式发送帧中继信息。静态映射。(注意:对方IP和己方DLCI)
 frame-relay map ip 134.1.1.4 104 broadcast
 no frame-relay inverse-arp                 关闭自动映射。
router ospf 1
 log-adjacency-changes
 network 1.1.1.0 0.0.0.255 area 0
 network 134.1.1.0 0.0.0.255 area 0
 neighbor 134.1.1.3 priority 3          在NBMA的网络中,只能使用neighbor来指明邻居还可以指明邻居的优先级。
 neighbor 134.1.1.4
SWITCH:
frame-relay switching                  配置成帧中继交换机。此命令很重要。
interface Serial0/0
 no ip address
 encapsulation frame-relay              封装成帧中继
 clockrate 128000
 frame-relay lmi-type cisco              配置帧中继的类型
 frame-relay intf-type dce                配置帧中继为DCE
 frame-relay route 103 interface Serial0/1 301    做帧中继映射
 frame-relay route 104 interface Serial0/2 401
interface Serial0/1
 no ip address
 encapsulation frame-relay
 clockrate 128000
 frame-relay lmi-type cisco
 frame-relay intf-type dce
 frame-relay route 301 interface Serial0/0 103
interface Serial0/2
 no ip address
 encapsulation frame-relay
 clockrate 128000
 frame-relay lmi-type cisco
 frame-relay intf-type dce
 frame-relay route 401 interface Serial0/0 104
R3:
interface Loopback0
 ip address 3.3.3.3 255.255.255.0
 ip ospf network point-to-point
interface Serial0/1
 ip address 134.1.1.3 255.255.255.0
 encapsulation frame-relay
 ip ospf network non-broadcast
 ip ospf priority 3
 frame-relay map ip 134.1.1.1 301 broadcast
 frame-relay map ip 134.1.1.4 301 broadcast  
no frame-relay inverse-arp
router ospf 1
 log-adjacency-changes
 network 3.3.3.0 0.0.0.255 area 0
 network 134.1.1.0 0.0.0.255 area 0
R4:
interface Loopback0
 ip address 4.4.4.4 255.255.255.0
 ip ospf network point-to-point
interface Serial0/1
 ip address 134.1.1.4 255.255.255.0
 encapsulation frame-relay
 ip ospf network non-broadcast
 ip ospf priority 0
 frame-relay map ip 134.1.1.1 401 broadcast
 frame-relay map ip 134.1.1.3 401 broadcast
no frame-relay inverse-arp
router ospf 1
 log-adjacency-changes
 network 4.4.4.0 0.0.0.255 area 0
 network 134.1.1.0 0.0.0.255 area 0
实验结果:
R1#show ip ospf neighbor
Neighbor ID     Pri   State           Dead Time   Address         Interface
3.3.3.3           3   FULL/BDR        00:01:31    134.1.1.3       Serial0/0
4.4.4.4           0   FULL/DROTHER    00:01:57    134.1.1.4       Serial0/0
R1#show ip route ospf
     3.0.0.0/24 is subnetted, 1 subnets
O       3.3.3.0 [110/782] via 134.1.1.3, 00:11:56, Serial0/0
     4.0.0.0/24 is subnetted, 1 subnets
O       4.4.4.0 [110/782] via 134.1.1.4, 00:11:56, Serial0/0
R3:frame-relay map ip 134.1.1.4 301 broadcast  
R4:frame-relay map ip 134.1.1.3 401 broadcast
以上两条命令的说明:
如果你加这两条命令,在R3上和R4上都能看见带O的路由,如:
R3#show ip route ospf
     1.0.0.0/24 is subnetted, 1 subnets
O       1.1.1.0 [110/782] via 134.1.1.1, 00:00:16, Serial0/1
     4.0.0.0/24 is subnetted, 1 subnets
O       4.4.4.0 [110/782] via 134.1.1.4, 00:00:16, Serial0/1
R3#ping 4.4.4.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R4#show ip route ospf
     1.0.0.0/24 is subnetted, 1 subnets
O       1.1.1.0 [110/782] via 134.1.1.1, 00:00:35, Serial0/1
     3.0.0.0/24 is subnetted, 1 subnets
O       3.3.3.0 [110/782] via 134.1.1.3, 00:00:35, Serial0/1
R4#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)
说明即使有路由,但是没有帧中继映射还是不能够通信。
加上这两条命令后:
R3#show ip route ospf
     1.0.0.0/24 is subnetted, 1 subnets
O       1.1.1.0 [110/782] via 134.1.1.1, 00:04:15, Serial0/1
     4.0.0.0/24 is subnetted, 1 subnets
O       4.4.4.0 [110/782] via 134.1.1.4, 00:04:15, Serial0/1
R3#ping 4.4.4.4
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/57/60 ms
R4#show ip route ospf
     1.0.0.0/24 is subnetted, 1 subnets
O       1.1.1.0 [110/782] via 134.1.1.1, 00:03:57, Serial0/1
     3.0.0.0/24 is subnetted, 1 subnets
O       3.3.3.0 [110/782] via 134.1.1.3, 00:03:57, Serial0/1
R4#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 100 percent (5/5), round-trip min/avg/max = 56/57/60 ms