实验介绍
辅助理解OSPF的虚链路
实验目的
-
探索VLink的使用
拓扑结构
接口信息
实验步骤
步骤一:配置基本信息
以R1为例,其余类似
[R1-GigabitEthernet0/0/0]dis th
[V200R003C00]
#
interface GigabitEthernet0/0/0
ip address 10.1.1.1 255.255.255.0
#
return
[R1-LoopBack0]dis th
[V200R003C00]
#
interface LoopBack0
ip address 1.1.1.1 255.255.255.255
#
return
步骤二:配置OSPF
以R2为例,其余类似
[R2-ospf-1]dis th
[V200R003C00]
#
ospf 1 router-id 2.2.2.2
area 0.0.0.0
network 10.1.1.2 0.0.0.0
area 0.0.0.1
network 20.1.1.1 0.0.0.0
#
return
步骤三:配置VLink
配置前
除在区域0的R1
和与区域0相连区域1的R3
有OSPF路由,其余路由器均学习不到OSPF路由。
[R1]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 1 Routes : 1
OSPF routing table status : <Active>
Destinations : 1 Routes : 1
Destination/Mask Proto Pre Cost Flags NextHop Interface
20.1.1.0/24 OSPF 10 2 D 10.1.1.2 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
[R3-ospf-1-area-0.0.0.1]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 1 Routes : 1
OSPF routing table status : <Active>
Destinations : 1 Routes : 1
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.0/24 OSPF 10 2 D 20.1.1.1 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
同一网段为直连故不通过OSPF学习。
[R2-ospf-1]dis ip routing-table protocol ospf
[R2-ospf-1]
[R6-ospf-1-area-0.0.0.4]dis ip routing-table protocol ospf
[R6-ospf-1-area-0.0.0.4]
配置区域2与区域0的虚链路
配置前
位于区域2的R4学习不到OSPF路由
[R4-ospf-1-area-0.0.0.3]dis ip routing-table protocol ospf
[R4-ospf-1-area-0.0.0.3]
配置虚链路
区域2想要与区域0相连,需要穿过区域1,故要在区域1两端建立虚链路
[R2-ospf-1-area-0.0.0.1]dis th
[V200R003C00]
#
area 0.0.0.1
network 20.1.1.1 0.0.0.0
vlink-peer 3.3.3.3
#
return
[R3-ospf-1-area-0.0.0.1]dis th
[V200R003C00]
#
area 0.0.0.1
network 20.1.1.2 0.0.0.0
vlink-peer 2.2.2.2
#
return
扩展
虚链路创建后的OSPF邻居建立过程中没有2-Way状态,因为早已确定主从关系了。
[R2-ospf-1-area-0.0.0.1]
Oct 2 2025 10:22:04-08:00 R2 %%01OSPF/4/VLINK_NBR_CHG_E(l)[14]:Virtual link peer event: neighbor status changed. (ProcessId=256, VirtualLinkNeighborAddress=3.3.3.3, NeighborEvent=HelloReceived, NeighborPreviousState=Down, NeighborCurrentState=Init)
[R2-ospf-1-area-0.0.0.1]
Oct 2 2025 10:22:04-08:00 R2 %%01OSPF/4/VLINK_NBR_CHG_E(l)[15]:Virtual link peer event: neighbor status changed. (ProcessId=256, VirtualLinkNeighborAddress=3.3.3.3, NeighborEvent=2WayReceived, NeighborPreviousState=Init, NeighborCurrentState=ExStart)
[R2-ospf-1-area-0.0.0.1]
Oct 2 2025 10:22:04-08:00 R2 %%01OSPF/4/VLINK_NBR_CHG_E(l)[16]:Virtual link peer event: neighbor status changed. (ProcessId=256, VirtualLinkNeighborAddress=3.3.3.3, NeighborEvent=NegotiationDone, NeighborPreviousState=ExStart, NeighborCurrentState=Exchange)
[R2-ospf-1-area-0.0.0.1]
Oct 2 2025 10:22:04-08:00 R2 %%01OSPF/4/VLINK_NBR_CHG_E(l)[17]:Virtual link peer event: neighbor status changed. (ProcessId=256, VirtualLinkNeighborAddress=3.3.3.3, NeighborEvent=ExchangeDone, NeighborPreviousState=Exchange, NeighborCurrentState=Loading)
[R2-ospf-1-area-0.0.0.1]
Oct 2 2025 10:22:04-08:00 R2 %%01OSPF/4/VLINK_NBR_CHG_E(l)[18]:Virtual link peer event: neighbor status changed. (ProcessId=256, VirtualLinkNeighborAddress=3.3.3.3, NeighborEvent=LoadingDone, NeighborPreviousState=Loading, NeighborCurrentState=Full)
配置后
R4成功通过OSPF学习到了路由。
至此区域0、区域1和区域2之间能正常通信。
[R4-ospf-1-area-0.0.0.3]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 2 Routes : 2
OSPF routing table status : <Active>
Destinations : 2 Routes : 2
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.0/24 OSPF 10 3 D 30.1.1.1 GigabitEthernet0/0/0
20.1.1.0/24 OSPF 10 2 D 30.1.1.1 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
[R1]dis ip routing-table protocol ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 2 Routes : 2
OSPF routing table status : <Active>
Destinations : 2 Routes : 2
Destination/Mask Proto Pre Cost Flags NextHop Interface
20.1.1.0/24 OSPF 10 2 D 10.1.1.2 GigabitEthernet0/0/0
30.1.1.0/24 OSPF 10 3 D 10.1.1.2 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
配置区域3与区域0的虚链路
配置前
位于区域2的R5学习不到其他OSPF路由
[R5-ospf-1-area-0.0.0.4]dis ip rou p ospf
[R5-ospf-1-area-0.0.0.4]
配置虚链路
区域3想要与区域0相连,需要穿过区域1和区域2,区域1已经配置完虚链路了,故要在区域2两端建立虚链路
[R3-ospf-1-area-0.0.0.2]dis th
[V200R003C00]
#
area 0.0.0.2
network 30.1.1.1 0.0.0.0
vlink-peer 4.4.4.4
#
return
[R4-ospf-1-area-0.0.0.2]dis th
[V200R003C00]
#
area 0.0.0.2
network 30.1.1.2 0.0.0.0
vlink-peer 3.3.3.3
#
return
配置后
R5成功通过OSPF学习到了路由。
至此区域0、区域1、区域2和区域3之间能正常通信。
[R5-ospf-1-area-0.0.0.4]dis ip rou p ospf
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : OSPF
Destinations : 3 Routes : 3
OSPF routing table status : <Active>
Destinations : 3 Routes : 3
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.0/24 OSPF 10 4 D 40.1.1.1 GigabitEthernet0/0/0
20.1.1.0/24 OSPF 10 3 D 40.1.1.1 GigabitEthernet0/0/0
30.1.1.0/24 OSPF 10 2 D 40.1.1.1 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
配置区域3与区域0的虚链路
配置前
位于区域3的R6学习不到OSPF路由
[R6-ospf-1-area-0.0.0.4]dis ip routing-table protocol ospf
[R6-ospf-1-area-0.0.0.4]
配置虚链路
区域4想要与区域0相连,需要穿过区域1、区域2和区域3,区域1和区域2已经配置完虚链路了,故要在区域3两端建立虚链路
[R4-ospf-1-area-0.0.0.3]dis th
[V200R003C00]
#
area 0.0.0.3
network 40.1.1.1 0.0.0.0
vlink-peer 5.5.5.5
#
return
[R5-ospf-1-area-0.0.0.3]dis th
[V200R003C00]
#
area 0.0.0.3
network 40.1.1.2 0.0.0.0
vlink-peer 4.4.4.4
#
return
配置后
R6成功通过OSPF学习到了路由。
至此全部OSPF区域之间能正常通信。
所有的路由器均能通过OSPF学习到全拓扑的明细路由。
[R6-ospf-1]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 : 4
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.1.0/24 OSPF 10 5 D 50.1.1.1 GigabitEthernet0/0/0
20.1.1.0/24 OSPF 10 4 D 50.1.1.1 GigabitEthernet0/0/0
30.1.1.0/24 OSPF 10 3 D 50.1.1.1 GigabitEthernet0/0/0
40.1.1.0/24 OSPF 10 2 D 50.1.1.1 GigabitEthernet0/0/0
OSPF routing table status : <Inactive>
Destinations : 0 Routes : 0
步骤四:验证
通信验证
R1与R6正常通信
[R1]tracert -a 10.1.1.1 50.1.1.2
traceroute to 50.1.1.2(50.1.1.2), max hops: 30 ,packet length: 40,press CTRL_C to break
1 10.1.1.2 30 ms 20 ms 20 ms
2 20.1.1.2 40 ms 30 ms 20 ms
3 30.1.1.2 30 ms 30 ms 30 ms
4 40.1.1.2 60 ms 30 ms 30 ms
5 50.1.1.2 40 ms 50 ms 40 ms
虚链路详情
在R2上
[R2]dis ospf vlink
OSPF Process 1 with Router ID 2.2.2.2
Virtual Links
Virtual-link Neighbor-id -> 3.3.3.3, Neighbor-State: Full
Interface: 20.1.1.1 (GigabitEthernet0/0/1)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.1
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal
在R3上
[R3]dis ospf vlink
OSPF Process 1 with Router ID 3.3.3.3
Virtual Links
Virtual-link Neighbor-id -> 2.2.2.2, Neighbor-State: Full
Interface: 20.1.1.2 (GigabitEthernet0/0/0)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.1
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal
Virtual Links
Virtual-link Neighbor-id -> 4.4.4.4, Neighbor-State: Full
Interface: 30.1.1.1 (GigabitEthernet0/0/1)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.2
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal
在R4上
[R4]dis ospf vlink
OSPF Process 1 with Router ID 4.4.4.4
Virtual Links
Virtual-link Neighbor-id -> 3.3.3.3, Neighbor-State: Full
Interface: 30.1.1.2 (GigabitEthernet0/0/0)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.2
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal
Virtual Links
Virtual-link Neighbor-id -> 5.5.5.5, Neighbor-State: Full
Interface: 40.1.1.1 (GigabitEthernet0/0/1)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.3
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal
在R5上
[R5]dis ospf vlink
OSPF Process 1 with Router ID 5.5.5.5
Virtual Links
Virtual-link Neighbor-id -> 4.4.4.4, Neighbor-State: Full
Interface: 40.1.1.2 (GigabitEthernet0/0/0)
Cost: 1 State: P-2-P Type: Virtual
Transit Area: 0.0.0.3
Timers: Hello 10 , Dead 40 , Retransmit 5 , Transmit Delay 1
GR State: Normal