• OSPF(Open Shortest Path First開放式最短路徑優先）是一個內部閘道器協議(Interior Gateway Protocol，簡稱IGP）,在企業內網當中應用非常廣泛，本位主要介紹OSPF多區域配，以及OSPF鏈路狀態資料庫基本分析，OSPF多區域的產生可以增強網路的可擴充套件性、降低路由器的負載、快速收斂。

• 拓撲配如下圖：
  

  每臺路由器基本網路配置如下：

  R1配置：
  system-view
  sysname R1
  user-interface console 0
  idle-timeout 1000
  quit
  interface GigabitEthernet0/0/2
  ip address 192.168.1.254 255.255.255.0
  interface GigabitEthernet0/0/1
  ip address 192.168.17.1 255.255.255.0
  interface GigabitEthernet0/0/0
  ip address 192.168.12.1 255.255.255.0
  quit

  R2配置：
  system-view
  sysname R2
  interface GigabitEthernet0/0/1
  ip address 192.168.12.2 255.255.255.0
  interface GigabitEthernet0/0/0
  ip address 192.168.23.2 255.255.255.0
  quit
  R3配置：
  system-view
  sysname R3
  interface GigabitEthernet0/0/1
  ip address 192.168.23.3 255.255.255.0
  interface GigabitEthernet0/0/0
  ip address 192.168.34.3 255.255.255.0
  quit

  R4配置：
  system-view
  sysname R4
  interface GigabitEthernet0/0/1
  ip address 192.168.34.4 255.255.255.0
  interface GigabitEthernet0/0/0
  ip address 192.168.45.4 255.255.255.0
  quit

  R5配置：
  system-view
  sysname R5
  interface GigabitEthernet0/0/1
  ip address 192.168.45.5 255.255.255.0
  interface GigabitEthernet0/0/2
  ip address 192.168.5.254 255.255.255.0
  interface GigabitEthernet0/0/0
  ip address 100.1.1.5 255.255.255.0

  PC1、PC2配置如下：
  
  

  接下來我們配置OSPF多區域，配置如下：

  R1配置
  ospf 1 router-id 1.1.1.1
  area 12
  network 192.168.12.0 0.0.0.255
  network 192.168.1.0 0.0.0.255

  R2配置
  ospf 1 router-id 2.2.2.2
  area 0
  network 192.168.23.0 0.0.0.255
  area 12
  network 192.168.12.0 0.0.0.255

  R3配置
  ospf 1 router-id 3.3.3.3
  area 0
  network 192.168.23.0 0.0.0.255
  network 192.168.34.0 0.0.0.255

  R4配置
  ospf 1 router-id 4.4.4.4
  area 0
  network 192.168.34.0 0.0.0.255
  area 45
  network 192.168.45.0 0.0.0.255

  R5配置
  ospf 1 router-id 5.5.5.5
  area 45
  network 192.168.45.0 0.0.0.255
  network 192.168.5.0 0.0.0.255

  測試讓了連通性，用PC1pingPC2，網路互通，如下：
  

  檢視R1的鏈路狀態資料庫如下：

[R1]display ospf lsdb
OSPF Process 1 with Router ID 1.1.1.1
Link State Database

                     Area: 0.0.0.12

Type LinkState ID AdvRouter Age Len Sequence Metric
Router 2.2.2.2 2.2.2.2 1423 36 80000004 1
Router 1.1.1.1 1.1.1.1 1012 48 80000008 1
Network 192.168.12.2 2.2.2.2 1423 32 80000002 0
Sum-Net 192.168.5.0 2.2.2.2 1039 28 80000001 4
Sum-Net 192.168.45.0 2.2.2.2 1409 28 80000001 3
Sum-Net 192.168.23.0 2.2.2.2 1468 28 80000001 1
Sum-Net 192.168.34.0 2.2.2.2 1409 28 80000001 2
Sum-Asbr 5.5.5.5 2.2.2.2 1393 28 80000001 3

 檢視R2的鏈路狀態資料庫如下：

[R1]display ospf lsdb
OSPF Process 1 with Router ID 2.2.2.2
Link State Database

             Area: 0.0.0.0

Type LinkState ID AdvRouter Age Len Sequence Metric
Router 4.4.4.4 4.4.4.4 1323 36 80000005 1
Router 2.2.2.2 2.2.2.2 1332 36 80000005 1
Router 3.3.3.3 3.3.3.3 1322 48 80000008 1
Network 192.168.23.3 3.3.3.3 1323 32 80000002 0
Network 192.168.34.4 4.4.4.4 1324 32 80000002 0
Sum-Net 192.168.5.0 4.4.4.4 954 28 80000001 2
Sum-Net 192.168.45.0 4.4.4.4 1361 28 80000001 1
Sum-Net 192.168.12.0 2.2.2.2 1381 28 80000001 1
Sum-Net 192.168.1.0 2.2.2.2 964 28 80000001 2
Sum-Asbr 5.5.5.5 4.4.4.4 1308 28 80000001 1

    Area: 0.0.0.12

Type LinkState ID AdvRouter Age Len Sequence Metric
Router 2.2.2.2 2.2.2.2 1336 36 80000004 1
Router 1.1.1.1 1.1.1.1 927 48 80000008 1
Network 192.168.12.2 2.2.2.2 1336 32 80000002 0
Sum-Net 192.168.5.0 2.2.2.2 952 28 80000001 4
Sum-Net 192.168.45.0 2.2.2.2 1322 28 80000001 3
Sum-Net 192.168.23.0 2.2.2.2 1381 28 80000001 1
Sum-Net 192.168.34.0 2.2.2.2 1322 28 80000001 2
Sum-Asbr 5.5.5.5 2.2.2.2 1306 28 80000001 3

• OSPF路由器分類：區域內部路由器、區域間路由器（ABR如R2和R4、ASBR如R5）、區域外部路由器。
• OSPF區域型別：骨幹區域，非骨幹區域，非骨幹區域又分為：標準區域、特殊區域
• OSPF路由分類：內部路由、外部路由。