OSPF Cannot Find Routes of a Non-Local Area
Procedure
- Check whether the area where the device resides is connected
to the backbone area.
Run the display ospf [ process-id ] brief command on the ABR in the area where the device resides to check area configuration.
OSPF requires that all non-backbone areas remain connected to the backbone area.
If no backbone area information is configured on the ABR, run the area area-id command in the OSPF view to modify the OSPF area information. Ensure that at least one interface on the ABR runs in the backbone area.
If some non-backbone areas cannot be connected to the backbone area due to networking restrictions, configure OSPF virtual links to resolve this problem.
- Check whether the area where the device resides is a totally
stub area.
Run the display current-configuration configuration ospf [ process-id ] command on the device to check the OSPF process configuration.
If you specify the parameter no-summary (run the stub no-summary command in the OSPF area view) when configuring a non-backbone area as a stub area on the ABR, the area is configured as a totally stub area.
A totally stub area allows only intra-area routes to be advertised within the area.
If the area where the device resides is configured as a totally stub area, perform the following configuration based on service requirements:To restore the totally stub area to a common area, run the undo stub command in the OSPF area view on all devices in the area.
To restore a totally stub area to a stub area, run the undo stub command in the OSPF area view on the ABR in the area and then run the stub command.
- Check whether the area where the device resides is a totally
NSSA.
Run the display current-configuration configuration ospf [ process-id ] command on the device to check the OSPF process configuration.
If you specify the parameter no-summary (run the nssa no-summary command in the OSPF area view) when configuring a non-backbone area as an NSSA on the ABR, the area is configured as a totally NSSA.
A totally NSSA allows only intra-area routes to be advertised within the area.
If the area where the device resides is configured as a totally NSSA, perform the following configuration based on service requirements:To restore the totally NSSA to a common area, run the undo nssa command in the OSPF area view on all devices in the area.
To restore a totally NSSA to a stub area, run the undo nssa command in the OSPF area view on the ABR in the area and then run the nssa command.