验证理论：
1.剖析OSPF的三张表：邻居表，拓扑表，路由表
dis ospf peer brief
dis ospf lsdb
dis ip routing-table protocol ospf
2.查看OSPF路由器的角色
dis ospf abr-asbr
3.OSPFrouter id选举机制
1.手动指定
2.选择loopback接口（选择较大IP，是否在OSPF进程中并不重要）
3.选择物理接口（选择较大IP,是否在OSPF进程中并不重要）
*123规则，先配置会优先生效
*router-id选举机制不具有抢占性。修改router-id如果要生效的话需要重启进程生效reset ospf process
*查看router-id命令：dis ospf peer brief
实验拓扑：
初始配置：
*说明，为方便后面验证router-id，AR123都是先在互联接口上使能OSPF
[AR3]ip route-static 150.1.4.4 32 155.1.34.4
[AR3-ospf-1]import-route static
[AR4]ip route-static 0.0.0.0 0.0.0.0 155.1.34.3初始结果：
[AR1]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 4 Routes : 4 OSPF routing table status : <Active>
Destinations : 4 Routes : 4Destination/Mask Proto Pre Cost Flags NextHop Interface
150.1.2.2/32 OSPF 10 1 D 155.1.12.2 GigabitEthernet0/0/0
150.1.3.3/32 OSPF 10 2 D 155.1.12.2 GigabitEthernet0/0/0
150.1.4.4/32 O_ASE 150 1 D 155.1.12.2 GigabitEthernet0/0/0
155.1.23.0/24 OSPF 10 2 D 155.1.12.2 GigabitEthernet0/0/0OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0一.
实验目的：
剖析OSPF三张表项
1.邻居表-dis ospf peer
[AR3]dis ospf peer brief
OSPF Process 1 with Router ID 155.1.23.3
Peer Statistic Information
----------------------------------------------------------------------------
Area Id Interface Neighbor id State
0.0.0.0 GigabitEthernet0/0/1 155.1.12.2 Full
----------------------------------------------------------------------------可查看信息：
1.该邻居是在本地的哪个OSPF进程内:OSPF Process 1
2.本路由器的router-id:Router ID 155.1.23.3
3.接口及邻居互联接口所属区域：Area Id
4.本路由器用来和邻居建立关系的接口：Interface
5.邻居的router-id: Neighbor id
6.本路由器与邻居建立的关系当前的状态：State
扩展：dis ospf peer
[AR3]dis ospf peer
OSPF Process 1 with Router ID 155.1.23.3
Neighbors Area 0.0.0.0 interface 155.1.23.3(GigabitEthernet0/0/1)'s neighbors
Router ID: 155.1.12.2 Address: 155.1.23.2
State: Full Mode:Nbr is Slave Priority: 1
DR: 155.1.23.3 BDR: 155.1.23.2 MTU: 0
Dead timer due in 31 sec
Retrans timer interval: 5
Neighbor is up for 00:05:00
Authentication Sequence: [ 0 ]
可查看信息：
1.该邻居是在本地的哪个OSPF进程内+本路由器的router-id：OSPF Process 1 with Router ID 155.1.23.3
2.接口及邻居互联接口所属区域+本路由器用来和邻居建立关系的接口地址和接口号：Area 0.0.0.0 interface 155.1.23.3(GigabitEthernet0/0/1)'s neighbors
3.邻居router id+邻居与本路由器互联接口的IP地址：Router ID: 155.1.12.2 Address: 155.1.23.2
4.本路由器与邻居建立的关系当前的状态+主从选举结果
5.邻居状态（可能为down,attempt,init,two-way,exstart,exchange,loading,full）+邻居在进行DD报文选举过程中的主从状态，邻居的优先级：State: Full Mode:Nbr is Slave Priority: 1
6.指定路由器地址，备份路由器地址，邻居接口MTU的值：DR: 155.1.23.3 BDR: 155.1.23.2 MTU: 0
7.dead计时器在31s后到时：Dead timer due in 31 sec
8.重传LSA的时间间隔，单位为秒：Retrans timer interval: 5
9.距离邻居建立的时间：Neighbor is up for 00:05:00
10.认证序列号：Authentication Sequence: [ 0 ]
2.拓扑表
dis ospf lsdb
[AR1]dis ospf lsdb
OSPF Process 1 with Router ID 155.1.12.1
Link State Database Area: 0.0.0.1
Type LinkState ID AdvRouter Age Len Sequence Metric
Router 155.1.12.2 155.1.12.2 982 48 80000005 1
Router 155.1.12.1 155.1.12.1 981 48 80000004 1
Network 155.1.12.2 155.1.12.2 982 32 80000001 0
Sum-Net 150.1.3.3 155.1.12.2 968 28 80000001 1
Sum-Net 155.1.23.0 155.1.12.2 1006 28 80000001 1
Sum-Asbr 155.1.34.3 155.1.12.2 68 28 80000001 1 AS External Database
Type LinkState ID AdvRouter Age Len Sequence Metric
External 150.1.4.4 155.1.34.3 1004 36 80000001 1可查看信息：
1.该邻居是在本地的哪个OSPF进程内+本路由器的router-id：OSPF Process 1 with Router ID 155.1.12.1
2.显示LSDB信息的区域：Area: 0.0.0.1
3.LSA类型（Router/Network/Sum-Net/Sum-Asbr/NSSA/External/Opq-Link/Opq-Area/Opq-As）：type
4.LSA报头中的链路状态ID:LinkState ID
5.发布或产生LSA的设备:AdvRouter
6.Lsa老化时间，Lsa大小，Lsa序列号：age ,length,sequence
7.度量值：Metric
3.路由表
dis ip routing-table protocol ospf
[AR1]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 4 Routes : 4 OSPF routing table status : <Active>
Destinations : 4 Routes : 4Destination/Mask Proto Pre Cost Flags NextHop Interface
150.1.2.2/32 OSPF 10 1 D 155.1.12.2 GigabitEthernet0/0/0
150.1.3.3/32 OSPF 10 2 D 155.1.12.2 GigabitEthernet0/0/0
150.1.4.4/32 O_ASE 150 1 D 155.1.12.2 GigabitEthernet0/0/0
155.1.23.0/24 OSPF 10 2 D 155.1.12.2 GigabitEthernet0/0/0OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0可查看信息：
proto为协议,ospf代表OSPF自己学到的，O-ASE代表外部引入的
二.
实验目的：
查看路由器角色
实验步骤：
dis ospf abr-asbr
[AR1]dis ospf abr-asbr
OSPF Process 1 with Router ID 155.1.12.1
Routing Table to ABR and ASBR RtType Destination Area Cost Nexthop Type
Intra-area 155.1.12.2 0.0.0.1 1 155.1.12.2 ABR
Inter-area 155.1.34.3 0.0.0.1 2 155.1.12.2 ASBR
可查看信息：
1.表示区域内路由器或者是区域间路由器：RtType
2.显示ABR或者ASBR的router-id: Destination
3.本地区域号： Area
4.从设备到达ABR或ASBR的开销： Cost
5.发送报文到ABR或ASBR的下一跳IP地址：Nexthop
6.区域边界路由器（ABR）或自治系统边界路由器（ASBR）：Type
三.
实验目的：
验证OSPF router-id选举机制
1.手动指定
2.选择loopback接口（选择较大IP，是否在OSPF进程中并不重要）
3.选择物理接口（选择较大IP,是否在OSPF进程中并不重要）
*123规则，先配置会优先生效
*router-id选举机制不具有抢占性。修改router-id如果要生效的话需要重启进程生效reset ospf process
*查看router-id命令：dis ospf peer brief
实验步骤：
第一步：因为是先在互联口上enable的ospf，所以现在OSPF的router id 都是互联口了
所以，先配先成为router-id
第二步：AR1重启OSPF进程
<AR1>reset ospf process
[AR1]dis ospf peer brief
OSPF Process 1 with Router ID 155.1.12.1
Peer Statistic Information
----------------------------------------------------------------------------
Area Id Interface Neighbor id State
0.0.0.1 GigabitEthernet0/0/0 155.1.12.2 Full
----------------------------------------------------------------------------仍然是互联口router-id。保存配置后重启路由器，仍然是互联口router-id，动态选举未验证成功
此时手动指定router-id并重置路由进程
[AR3]ospf router-id 150.1.3.3
[AR3]dis ospf peer brief
OSPF Process 1 with Router ID 150.1.3.3所以，手动指定优于动态选举
将lo 0口移出OSPF，查看OSPF的router id是否发生变化
[AR3-LoopBack0]undo ospf en a 0
[AR3]dis ospf peer brief
OSPF Process 1 with Router ID 150.1.3.3所以，ospf的router id与接口是否在进程中并没有关系
将Lo 0 口地址删除并重启OSPF进程，查看OSPF的router id是否发生变化
[AR3-LoopBack0]undo ip add
[AR3]dis ospf peer brief
OSPF Process 1 with Router ID 150.1.3.3所以，OSPF手动指定rouer id ，这个只是作为路由器标识，只要不重复，即使不存在于这个路由器上都没关系
