1. 每台设备上配置接口以及环回口地址：

R1:

interface GigabitEthernet0/0/0

ip address 10.0.12.1 255.255.255.0

#

interface GigabitEthernet0/0/1

ip address 10.0.13.1 255.255.255.0

#

interface LoopBack0

ip address 10.0.1.1 255.255.255.255

R2:

interface GigabitEthernet0/0/0

ip address 10.0.12.2 255.255.255.0

#

interface GigabitEthernet0/0/2

ip address 10.0.23.2 255.255.255.0

#

interface LoopBack0

ip address 10.0.2.2 255.255.255.255

R3:

interface GigabitEthernet0/0/0

ip address 10.0.34.3 255.255.255.0

#

interface GigabitEthernet0/0/1

ip address 10.0.13.3 255.255.255.0

#

interface GigabitEthernet0/0/2

ip address 10.0.23.3 255.255.255.0

#

interface LoopBack0

ip address 10.0.3.3 255.255.255.255

R4:

interface GigabitEthernet0/0/0

ip address 10.0.34.4 255.255.255.0

#

interface LoopBack0

ip address 10.0.4.4 255.255.255.255

2. 每台设备上配置ospf协议，并划好区域：

R1:

ospf 1 router-id 10.0.1.1

area 0.0.0.0

network 10.0.12.0 0.0.0.255

network 10.0.1.1 0.0.0.0

area 0.0.0.1

network 10.0.13.0 0.0.0.255

R2:

ospf 1 router-id 10.0.2.2

area 0.0.0.0

network 10.0.2.2 0.0.0.0

network 10.0.12.0 0.0.0.255

area 0.0.0.1

network 10.0.23.0 0.0.0.255

R3:

ospf 1 router-id 10.0.3.3

area 0.0.0.1

network 10.0.3.3 0.0.0.0

network 10.0.23.0 0.0.0.255

network 10.0.13.0 0.0.0.255

area 0.0.0.2

network 10.0.34.0 0.0.0.255

R4:

ospf 1 router-id 10.0.4.4

area 0.0.0.2

network 10.0.4.4 0.0.0.0

network 10.0.34.0 0.0.0.255

3. 使用虚链路使区域2与区域-逻辑相连：

R1:

ospf 1

area 0.0.0.1

vlink-peer 10.0.3.3

R2:

ospf 1

area 0.0.0.1

vlink-peer 10.0.3.3

R3:

ospf 1

area 0.0.0.1

vlink-peer 10.0.2.2

vlink-peer 10.0.1.1

此时R1、R2能ping通R4

[R1]ping 10.0.4.4

PING 10.0.4.4: 56 data bytes, press CTRL_C to break

Reply from 10.0.4.4: bytes=56 Sequence=1 ttl=254 time=40 ms

Reply from 10.0.4.4: bytes=56 Sequence=2 ttl=254 time=40 ms

4. 优先使用路径R4-R3-R1，并以R4-R3-R2路径为备份路径：

R3:

interface GigabitEthernet0/0/2

ospf cost 10

R2:

interface GigabitEthernet0/0/2

ospf cost 10

5. 使用虚链路作为区域0链路的冗余备份

目前，R1与R2之间只有单条链路连接，如果出现链路故障，就会导致区域0被分割的问题。为了解决这一问题，增强网络的可靠性，可以以区域1为传输区域，在R1与R2之间建立--条虚链路作为冗余备份。

R1:

ospf 1

area 0.0.0.1

vlink-peer 10.0.1.1

R2:

ospf 1

area 0.0.0.1

vlink-peer 10.0.2.2

6. 配置虚链路的认证功能

R1:

ospf 1

area 0.0.0.1

vlink-peer 10.0.3.3 hmac-md5 1 plain huawei

vlink-peer 10.0.2.2 hmac-md5 1 plain huawei

R2:

ospf 1

area 0.0.0.1

vlink-peer 10.0.1.1 hmac-md5 1 plain huawei

vlink-peer 10.0.3.3 hmac-md5 1 plain huawei

R3:

ospf 1

area 0.0.0.1

vlink-peer 10.0.1.1 hmac-md5 1 plain huawei

vlink-peer 10.0.2.2 hmac-md5 1 plain huawei

最终配置：

R1:

sysname R1

#

interface GigabitEthernet0/0/0

ip address 10.0.12.1 255.255.255.0

#

interface GigabitEthernet0/0/1

ip address 10.0.13.1 255.255.255.0

#

interface LoopBack0

ip address 10.0.1.1 255.255.255.255

#

ospf 1 router-id 10.0.1.1

area 0.0.0.0

network 10.0.12.0 0.0.0.255

network 10.0.1.1 0.0.0.0

area 0.0.0.1

network 10.0.13.0 0.0.0.255

vlink-peer 10.0.3.3 hmac-md5 1 plain huawei

vlink-peer 10.0.2.2 hmac-md5 1 plain huawei

#

R2:

sysname R2

#

interface GigabitEthernet0/0/0

ip address 10.0.12.2 255.255.255.0

#

interface GigabitEthernet0/0/2

ip address 10.0.23.2 255.255.255.0

ospf cost 10

#

interface LoopBack0

ip address 10.0.2.2 255.255.255.255

#

ospf 1 router-id 10.0.2.2

area 0.0.0.0

network 10.0.2.2 0.0.0.0

network 10.0.12.0 0.0.0.255

area 0.0.0.1

network 10.0.23.0 0.0.0.255

vlink-peer 10.0.1.1 hmac-md5 1 plain huawei

vlink-peer 10.0.3.3 hmac-md5 1 plain huawei

#

R3:

sysname R3

#

interface GigabitEthernet0/0/0

ip address 10.0.34.3 255.255.255.0

#

interface GigabitEthernet0/0/1

ip address 10.0.13.3 255.255.255.0

#

interface GigabitEthernet0/0/2

ip address 10.0.23.3 255.255.255.0

ospf cost 10

#

interface LoopBack0

ip address 10.0.3.3 255.255.255.255

#

ospf 1 router-id 10.0.3.3

area 0.0.0.1

network 10.0.3.3 0.0.0.0

network 10.0.23.0 0.0.0.255

network 10.0.13.0 0.0.0.255

vlink-peer 10.0.1.1 hmac-md5 1 plain huawei

vlink-peer 10.0.2.2 hmac-md5 1 plain huawei

area 0.0.0.2

network 10.0.34.0 0.0.0.255

#

R4:

sysname R4

#

interface GigabitEthernet0/0/0

ip address 10.0.34.4 255.255.255.0

#

interface LoopBack0

ip address 10.0.4.4 255.255.255.255

#

ospf 1 router-id 10.0.4.4

area 0.0.0.2

network 10.0.4.4 0.0.0.0

network 10.0.34.0 0.0.0.255

#