Consider the following diagram. All PVCs are active.
If the partial output of the show ip ospf neighbor command executed on Router A is as follows, which of the
following statements is TRUE?
RouterA# show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
220.127.116.11 1 FULL/DROTHER 00:00:13 10.20.10.21 SerialO
18.104.22.168 1 FULL/DR 00:00:51 10.20.10.22 SerialO
A. Router C and Router B will fail to have all OSPF routes in their tables.
B. All routing tables will be populated correctly.
C. Router A will be the DR.
D. Router C will be the DR.
The output of the command shows that Router C and Router B will fail to have all OSPF routes in their
tables. In a hub and spoke configuration, as depicted in the diagram, the hub router (Router A) should be
the designated router (DR) or the source of updates to the other routers. However, Router B is the DR, as
evidenced by the output of the show ip ospf neighbor command executed on Router A.
This situation could be rectified by setting Routers B and C with a priority of 0, which would disqualify them
from being the DR. After that, all routes could be distributed from the hub, which would have visibility of all
All routing tables will be populated correctly until the hub router is made the DR.
Neither Router A nor C will be the DR, since it is indicated that Router B is the DR in the output of the
Layer 3 Technologies
Configure and verify OSPF operations
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Examples and Technotes > Initial Configurations for OSPF over Frame Relay Subinterfaces
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