配置要求：
用OSPF使PC1與PC2互通
確定R2和R4狀態是不是ABR
確保區域456中僅有一個DR，沒有BDR
確保區域456DR地址爲56.6
確保區域12中沒有DR，切發送hello報文的時間爲5s
配置步驟：
1、 基本配置：配置PC地址、網關，路由接口地址
2、 PC1與PC2互通
1） 配置思路
區域0爲主幹區域，非主幹區域必須連接主幹區域
鄰居建立路由router-id不能一致，同網絡的區域、子網必須一致
路由器開啓OSPF，12.0在區域12,23.0、34.0在區域0、45.0、56.0在區域456
每個路由命名router-id
1.0,2.0網絡爲直連PC，無需發送OSPF報文，所有用import-route direct添加
AR2\AR4爲ABR區域邊緣路由器，配置時注意區域切換
2）配置步驟
AR1配置
ospf 1 router-id 1.1.1.1 //進入OSPF進程1，命名routerid
import-route direct//由於192.168.1.0連接PC無需接收OSPF報文，用import-route direct將直連路由加入
area 12 //進入區域12
network 192.168.12.0 0.0.0.255//將192.168.12.0加入OSPF
AR2配置
ospf 1 router-id 2.2.2.2 //進入OSPF進程1，命名routerid
area 12 //進入區域12
network 192.168.12.0 0.0.0.255//將192.168.12.0加入OSPF
area 0 //進入區域0
network 192.168.23.0 0.0.0.255//將192.168.23.0加入OSPF
AR3配置
ospf 1 router-id 3.3.3.3 //進入OSPF進程1，命名routerid
area 0 //進入區域0
network 192.168.23.0 0.0.0.255
network 192.168.34.0 0.0.0.255
AR4配置
ospf 1 router-id 4.4.4.4
area 0
network 192.168.34.0 0.0.0.255
area 456
network 192.168.45.0 0.0.0.255
AR5配置
ospf 1 router-id 5.5.5.5
area 456
network 192.168.45.0 0.0.0.255
network 192.168.56.0 0.0.0.255
AR6配置
ospf 1 router-id 6.6.6.6
import-route direct
area 456
network 192.168.56.0 0.0.0.255
3、 確保區域12中沒有DR，切發送hello報文的時間爲5s
1） 配置思路
DR、BDR是否存在取決於不同的網絡類型
鄰居建立Hello報文與dead時間必須相同
12.0網段直連的兩個接口網絡類型、hello報文長度一致
2）配置步驟
AR1配置：
int g 0/0/0
ospf timer hello 5
ospf network-type p2p
AR2配置
int g 0/0/1
ospf timer hello 5
ospf network-type p2p
4、確保區域456中僅有一個DR，沒有BDR，確保區域456DR地址爲56.6
1）配置思路
456區域有45.0與56.0兩個網段
修改45.0網段直連接口網絡類型，確保45.0網絡不需要DR\BDR
OSPF權限爲0,不參與DR、BDR選舉，修改56.5 OSPF權限爲0
AR6配置步驟
ospf dr-priority 0
效果：
0、PC1與PC2可通信
1、AR1信息
OSPF Process 1 with Router ID 1.1.1.1
RouterID: 1.1.1.1
Area: 0.0.0.12
Interface: 192.168.12.1 (GigabitEthernet0/0/0) --> 192.168.12.2
Cost: 1 State: P-2-P Type: P2P MTU: 1500
Timers: Hello 5 , Dead 20 , Poll 120 , Retransmit 5 , Transmit Delay 1
192.168.2.0/24 O_ASE 150 1 D 192.168.12.2 GigabitEthernet
2、AR2信息
OSPF Process 1 with Router ID 2.2.2.2
RouterID: 2.2.2.2 Border Router: AREA
Area: 0.0.0.0
Interface: 192.168.23.2 (GigabitEthernet0/0/0)
Cost: 1 State: DR Type: Broadcast MTU: 1500
Priority: 1
Designated Router: 192.168.23.2
Backup Designated Router: 192.168.23.3
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
Area: 0.0.0.12
Interface: 192.168.12.2 (GigabitEthernet0/0/1) --> 192.168.12.1
Cost: 1 State: P-2-P Type: P2P MTU: 1500
Timers: Hello 5 , Dead 20 , Poll 120 , Retransmit 5 , Transmit Delay 1
3、AR3信息
OSPF Process 1 with Router ID 3.3.3.3
RouterID: 3.3.3.3
Area: 0.0.0.0 (MPLS TE not enabled)
Interface: 192.168.23.3 (GigabitEthernet0/0/1)
Cost: 1 State: BDR Type: Broadcast MTU: 1500
Priority: 1
Designated Router: 192.168.23.2
Backup Designated Router: 192.168.23.3
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
Interface: 192.168.34.3 (GigabitEthernet0/0/0)
Cost: 1 State: DR Type: Broadcast MTU: 1500
Priority: 1
Designated Router: 192.168.34.3
Backup Designated Router: 192.168.34.4
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
4、AR4信息
OSPF Process 1 with Router ID 4.4.4.4
RouterID: 4.4.4.4 Border Router: AREA
Area: 0.0.0.0 (MPLS TE not enabled)
Interface: 192.168.34.4 (GigabitEthernet0/0/1)
Cost: 1 State: BDR Type: Broadcast MTU: 1500
Priority: 1
Designated Router: 192.168.34.3
Backup Designated Router: 192.168.34.4
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
Area: 0.0.1.200
Interface: 192.168.45.4 (GigabitEthernet0/0/0) --> 192.168.45.5
Cost: 1 State: P-2-P Type: P2P MTU: 1500
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
5、AR5信息
OSPF Process 1 with Router ID 5.5.5.5
RouterID: 5.5.5.5 Border Router:
Area: 0.0.1.200
Interface: 192.168.45.5 (GigabitEthernet0/0/1) --> 192.168.45.4
Cost: 1 State: P-2-P Type: P2P MTU: 1500
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
Interface: 192.168.56.5 (GigabitEthernet0/0/0)
Cost: 1 State: DROther Type: Broadcast MTU: 1500
Priority: 0
Designated Router: 192.168.56.6
Backup Designated Router: 0.0.0.0
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1
6、AR6信息
OSPF Process 1 with Router ID 6.6.6.6
RouterID: 6.6.6.6
Area: 0.0.1.200 (MPLS TE not enabled)
Interface: 192.168.56.6 (GigabitEthernet0/0/1)
Cost: 1 State: DR Type: Broadcast MTU: 1500
Priority: 1
Designated Router: 192.168.56.6
Backup Designated Router: 0.0.0.0
Timers: Hello 10 , Dead 40 , Poll 120 , Retransmit 5 , Transmit Delay 1