TOPO如下：
基本配置如下：
l
R1
l
R2
R1基本配置
|
interface Loopback0
ip address 1.1.1.1 255.255.255.0
!
interface Serial1/0
ip address 12.1.1.1 255.255.255.0
!
router ospf 10
log-adjacency-changes
network 1.1.1.0 0.0.0.255 area 0
network 12.1.1.0 0.0.0.255 area 0
|
R2基本配置
|
interface Loopback0
ip address 2.2.2.2 255.255.255.0
!
interface Serial2/0
ip address 12.1.1.2 255.255.255.0
!
router ospf 10
log-adjacency-changes
network 2.2.2.0 0.0.0.255 area 0
network 12.1.1.0 0.0.0.255 area 0
|
网络类型：点到点
工作方式
| 是否要选DR/BDR
| 是否要指定邻居
| 邻居形成快慢
|
点到点（默认）
| 否
| 否
| 快
|
广播
| 是
| 否
| 很慢，40秒左右
|
NBMA
| 是
| 是
| 很慢，20秒左右
|
点到多点
| 否
| 否
| 较快，7秒左右
|
点到多点非广播
| 否
| 是
| 快
|
测试⑴：点到点（默认）
查看端口的工作模式：
r1#sho ip os int
Serial1/0 is up, line protocol is up
Internet Address 12.1.1.1/24, Area 0
Process ID 10, Router ID 1.1.1.1, Network Type POINT_TO_POINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5（以下忽略）
查看邻居关系：没有DR/BDR选举
r1#sho ip os nei
Neighbor ID
Pri
State
Dead Time
Address
Interface
2.2.2.2
0
FULL/
-
00:00:32
12.1.1.2
Serial1/0
测试⑵：广播
在R1、R2上修改端口的工作模式为broadcast
r1(config-if)#ip os network broadcast
r2(config-if)#ip os network broadcast
查看端口的工作模式：
r1#sho ip os int
Serial1/0 is up, line protocol is up
Internet Address 12.1.1.1/24, Area 0
Process ID 10, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 64
Transmit Delay is 1 sec, State BDR, Priority 1
Designated Router (ID) 2.2.2.2, Interface address 12.1.1.2
Backup Designated router (ID) 1.1.1.1, Interface address 12.1.1.1
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
查看邻居关系：有DR/BDR选举
r1#sho ip os nei
Neighbor ID
Pri
State
Dead Time
Address
Interface
2.2.2.2
1
FULL/DR
00:00:31
12.1.1.2
Serial1/0
测试⑶：NBMA
在R1、R2上修改端口的工作模式并在R1上指定邻居（如果没有手动指定邻居，邻居关系起不来，邻居只要在一边指定）
r1(config-if)#ip os net non-broadcast
r1(config-if)#router os 10
r1(config-router)#nei 12.1.1.2
r2(config-if)#ip os net non-broadcast
查看端口工作模式
r1#sho ip os int
Serial1/0 is up, line protocol is up
Internet Address 123.1.1.1/24, Area 0
Process ID 10, 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 12.1.1.1
Backup Designated router (ID) 2.2.2.2, Interface address 12.1.1.2
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
（以下忽略）
查看邻居关系：有DR/BDR选举
r1#sho ip os nei
Neighbor ID
Pri
State
Dead Time
Address
Interface
2.2.2.2
1
FULL/DR
00:01:59
12.1.1.2
Serial1/0
测试⑷：点到多点
在R1、R2上修改端口的工作模式
R1(config-if)#ip ospf network point-to-multipoint
R2(config-if)#ip ospf network point-to-multipoint
查看端口工作模式：
r1#sho ip os int
Serial1/0 is up, line protocol is up
Internet Address 12.1.1.1/24, Area 0
Process ID 10, Router ID 1.1.1.1, Network Type POINT_TO_MULTIPOINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
（以下忽略）
查看邻居关系：没有DR/BDR选举
r1#sh ip os nei
Neighbor ID
Pri
State
Dead Time
Address
Interface
2.2.2.2
0
FULL/
-
00:01:58
123.1.1.2
Serial1/0
测试⑸：点到多点非广播
在R1、R2上修改端口的工作模式并在R1上指定邻居（如果没有手动指定邻居，邻居关系起不来，邻居只要在一边指定）
r1(config-if)#ip os network point-to-multipoint non-broadcast
r1(config)#router os 10
r1(config-router)#nei 12.1.1.2
r2(config-if)#ip os network point-to-multipoint non-broadcast
查看端口工作模式：注意，这里我们配置了点到多点非广播，但是查看端口时只显示点到多点
r2#sho ip os int
Serial2/0 is up, line protocol is up
Internet Address 12.1.1.2/24, Area 0
Process ID 10, Router ID 2.2.2.2, Network Type POINT_TO_MULTIPOINT, Cost: 64
Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
查看邻居关系：没有DR/BDR选举
r1#sho ip os nei
Neighbor ID
Pri
State
Dead Time
Address
2.2.2.2
0
FULL/
-
00:01:42
123.1.1.2
Serial1/0
总结：在点到点的网络类型中，ospf接口的5种工作方式都能形成邻居，在形成邻居关系的时间上有所差异。
帖子来自汤姆一通， yangrubing-ITAA QQ:383506128
