08-09-2011 05:14 AM - edited 03-04-2019 01:13 PM
Hi,
I am not able to connect a virtaul link to the backbone over a gns3. Please suggest if anything need to be changed. Every router are forming the adjacency but still not able to reach backbone Area0. Topology attached.
R1
interface Loopback0
ip address 1.1.1.1 255.255.255.255
!
interface Serial0/0
ip address 192.168.1.1 255.255.255.252
serial restart-delay 0
!
interface Serial0/1
ip address 172.16.1.1 255.255.255.252
serial restart-delay 0
!
interface Serial0/2
ip address 172.16.2.1 255.255.255.252
!
router ospf 1
log-adjacency-changes
area 1 virtual-link 2.2.2.2
network 1.1.1.1 0.0.0.0 area 0
network 172.16.1.0 0.0.0.3 area 0
network 192.168.1.0 0.0.0.3 area 1
**************
R2
R2#
interface Loopback0
ip address 2.2.2.2 255.255.255.0
!
interface Serial0/0
ip address 192.168.1.2 255.255.255.252
serial restart-delay 0
!
!
interface Ethernet1/0
ip address 10.1.2.2 255.255.255.0
full-duplex
!
!
router ospf 1
log-adjacency-changes
area 1 virtual-link 1.1.1.1
network 2.2.2.2 0.0.0.0 area 2
network 10.1.2.0 0.0.0.255 area 2
network 192.168.1.0 0.0.0.3 area 1
*****
R3
interface Loopback0
ip address 3.3.3.3 255.255.255.255
!
interface Serial0/0
ip address 172.16.1.2 255.255.255.252
serial restart-delay 0
!
interface Serial0/1
ip address 172.16.3.1 255.255.255.252
serial restart-delay 0
!
!
router ospf 1
log-adjacency-changes
network 3.3.3.3 0.0.0.0 area 0
network 172.16.1.0 0.0.0.3 area 0
network 172.16.3.0 0.0.0.3 area 0
******
Waiting for your suggestion. Thanks in advance.
Solved! Go to Solution.
08-09-2011 07:20 AM
Which is Area 1 and Area 2.
Pls refer here "OSPF Virtual Link"
http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00801ec9ee.shtml
Regards,
Sunil
Pls rate the post if you find the content useful.
08-09-2011 05:23 AM
Hello,
Please verify using the show ip ospf virtual-link whether the virtual link has come up. Quickly skimming over your configuration, there does not seem to be any obvious configuration problem but it is possible that your router IDs do not correspond to those used in the virtual link configuration. Use the show ip ospf to verify the RID on R1 and R2, and I also suggest fixing the RIDs using the OSPF configuration command router-id
Best regards,
Peter
08-09-2011 05:34 AM
Hi Peter,
Thanks for ur interest to give a sugesstion, please have a look i.e., RID are correctly set over VL.
R1#sh ip ospf
Routing Process "ospf 1" with ID 1.1.1.1
Start time: 00:00:11.948, Time elapsed: 01:49:03.548
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
It is an area border router
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
Number of areas transit capable is 1
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 3 (1 loopback)
Area has no authentication
SPF algorithm last executed 01:01:42.564 ago
SPF algorithm executed 3 times
Area ranges are
Number of LSA 8. Checksum Sum 0x05EBC8
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 4
Flood list length 0
Area 1
Number of interfaces in this area is 1
This area has transit capability: Virtual Link Endpoint
Area has no authentication
SPF algorithm last executed 01:01:42.572 ago
SPF algorithm executed 4 times
Area ranges are
Number of LSA 8. Checksum Sum 0x05569F
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
R1#sh ip ospf n
Neighbor ID Pri State Dead Time Address Interface
3.3.3.3 0 FULL/ - 00:00:33 172.16.1.2 Serial0/1
2.2.2.2 0 FULL/ - - 192.168.1.2 OSPF_VL0
2.2.2.2 0 FULL/ - 00:00:30 192.168.1.2 Serial0/0
**************
R2#sh ip ospf
Routing Process "ospf 1" with ID 2.2.2.2
Start time: 00:00:13.508, Time elapsed: 02:02:52.380
Supports only single TOS(TOS0) routes
Supports opaque LSA
Supports Link-local Signaling (LLS)
Supports area transit capability
It is an area border router
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Incremental-SPF disabled
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Number of external LSA 0. Checksum Sum 0x000000
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 3. 3 normal 0 stub 0 nssa
Number of areas transit capable is 1
R2#sh ip ospf n
Neighbor ID Pri State Dead Time Address Interface
1.1.1.1 0 FULL/ - - 192.168.1.1 OSPF_VL0
1.1.1.1 0 FULL/ - 00:00:32 192.168.1.1 Serial0/0
Please suggest still the RID needs to be hardcoded
08-09-2011 07:22 AM
What does "sh ip ospf virtual-links" show ?
Jon
08-09-2011 08:25 AM
Jon, Sanjay,
According to the show ip ospf neighbor output displayed by Sanjay, the OSPF adjacency has been fully established over the virtual link (see the OSPF_VL0 entry in the output) so I would say the virtual link itself should work correctly. The RIDs do not need to be hardcoded under these circumstances, although having them hardcoded is a best practice.
Sanjay, can you please be very specific about the issue you are trying to solve, i.e. show us exactly the routing table that is missing some route, etc.? So far your description of the problem has been somewhat vague - that "Every router are forming the adjacency but still not able to reach backbone Area0." Can you make that more precise?
Thank you!
Best regards,
Peter
08-09-2011 09:34 AM
Hi All,
Thanks to u all for giving me the update. Please find after changing the area Id in all the router things got resolved now my virtual Links are working.
R2
router ospf 1
log-adjacency-changes
area 1 virtual-link 3.3.3.3
network 2.2.2.2 0.0.0.0 area 2
network 10.1.2.0 0.0.0.255 area 2
network 192.168.1.0 0.0.0.3 area 1
R2#sh ip ospf n
Neighbor ID Pri State Dead Time Address Interface
3.3.3.3 0 FULL/ - - 172.16.1.2 OSPF_VL1
1.1.1.1 0 FULL/ - 00:00:36 192.168.1.1 Serial0/0
************
R1
router ospf 1
log-adjacency-changes
network 172.16.1.0 0.0.0.3 area 1
network 192.168.1.0 0.0.0.3 area 1
R1#sh ip ospf n
Neighbor ID Pri State Dead Time Address Interface
3.3.3.3 0 FULL/ - 00:00:35 172.16.1.2 Serial0/1
2.2.2.2 0 FULL/ - 00:00:38 192.168.1.2 Serial0/0
*****************
R3#sh run | b network
network 3.3.3.3 0.0.0.0 area 0
network 172.16.1.0 0.0.0.3 area 1
network 172.16.3.0 0.0.0.3 area 0
R3#sh ip ospf n
Neighbor ID Pri State Dead Time Address Interface
2.2.2.2 0 FULL/ - - 192.168.1.2 OSPF_VL3
1.1.1.1 0 FULL/ - 00:00:37 172.16.1.1 Serial0/0
***********************
Thanks 1 more times u all.
08-09-2011 07:20 AM
Which is Area 1 and Area 2.
Pls refer here "OSPF Virtual Link"
http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a00801ec9ee.shtml
Regards,
Sunil
Pls rate the post if you find the content useful.
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