21. OSPF related commands of layer 3 Technology-Virtual Link (3)
Virtual link: a link that connects to a backbone area through a non-backbone area.
Virtual links are generally used to:
V connects a region to the backbone area through a non-backbone area.
V connects some areas on both sides of a segmented backbone area through a non-backbone area.
Configure virtual link rules:
V virtual links must be configured between two routers.
The area through which the v virtual link passes must have all the routing information.
V transfer area cannot be a stub area and NSSA area.
The stability of v virtual link depends on the stability of the region it passes through.
V virtual links help provide logical redundancy.
CISCO Cisco OSPF related commands:
Command
Description
(config) # router ospf 110
Create and enter the OSPF process
(config-router) # router-id 1.1.1.1
Configure RouterID
(config-router) # network Segment reverse Mask Area0 (area number)
Declare the network segment
(config-router) # area 1 stub
Configuration area is stub area
(config-router) # area 1 stub no-summary
The configuration area is a complete stub area
(config-router) # redistribut rip subnets
Redistribute RIP to OSPF
(config-router) # redistribut ospf metric 5
Redistribute OSPF to RIP
(config-router) # default-information originate
Default route redistribution
(config-router) # area 2 nssa
Configuration area is NSSA area
(config-router) # area 2 nssa no-summary
The configuration area is a full NSSA area
(config-router) # area 2 nssa default-information-originate
Default route redistribution in NSSA area
(config-router) # area 1 range 192.168.0.0 255.255.0.0
Summary of interarea routes
(config-router) # summary-address 192.168.0.0 255.255.0.0
External route summary
(config-router) # area 1 (area to be traversed) virtual-links 1.1.1.1 (opposite RrouterID)
Virtual link
(config-if) # ip ospf priority 1
Configure OSPF interface priority
(config-if) # ip ospf cost 19
Cost of configuring OSPF interface
# show ip ospf neighbor
View neighbor tabl
# show ip ospf neighbor detail
View neighbor table summary information
# show ip ospf
View OSPF configuration
# show ip ospf interface type number
View the data structure of the interface
# show ip ospf interface brief
View summary information for the interface
# show ip ospf interface
View the information of the interface
# clear ip ospf precesses
Clear OSPF
# show ip ospf database
View link database status
# show ip ospf adj
View OSPF adjacency information
# show ip ospf packet
View each OSPF packet information
Note: when the interface Priority priority is 0, it does not participate in the election of DR and BDR.
Huawei H3C related orders:
Command
Description
[huawei] router id 1.1.1.1
Configure RrouterID
[huawei] ospf
Create and enter the OSPF process
[huawei-ospf-1] area 0
Configuration area
[huawei-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
Declare the network segment
[huawei-ospf-1-area-0.0.0.0] stub
Configuration area is stub area
[huawei-ospf-1-area-0.0.0.0] stub no-summay
The configuration area is a complete stub area
[huawei-ospf-1-area-0.0.0.0] nssa
Configuration area is NSSA area
[huawei] display ospf peer
View OSPF neighbor status
[huawei-ospf-1] import-route static type 1
Import static rout
[huawei] display ospf abr-asbr
View the information of ABR/ASBR
[huawei-Eth0/0/0] ospf dr-priority 1
Configure OSPF interface priority
[huawei] dispaly ospf interface
View OSPF interface status
