Refer to the exhibit. Router C was configured so that it could form an adjacency with three
OSPF neighbors, one connected to each of its three physical interfaces. Which statement is
correct about router C?
RouterC#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0/0 10.1.0.1 YES NVRAM up up
Serial0/0 10.255.255.253 YES NVRAM up up
Ethernet0/1 10.2.0.1 YES NVRAM up up
Loopback0 10.100.100.3 YES NVRAM up up
RouterC#
RouterC#show ip ospf
Routing Process “ospf 1” with ID 10.100.100.3
Supports onlu single TOS(TOS0) routes
Supports opage LSA
It is an area border router
SPF schedule delay 5 secs, Hold time between two SPF’s 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1secs
Number of external LSA 0. Checksume Sum 0x00000
Number of opaque AS LSA 0. Checksume Sum 0x00000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opague AS LSA 0
Number of areas in this router is 2. 1 normal 1 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 3
Area has no authentication
SPF algorithm executed 10 times
Area ramges are
Number of LSA 14. Checksume Sum 0x053D21
Number of opaque link LSA 0. Checksume Sum 0x00000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 4
Number of interfaces in this area is 1
It is a stub area, no summary LSA in this area
gemerates stub default route with cost 1
Area has no authentication
SPF algorithm executed 9 times
Area ramges are
Number of LSA 4. Checksume Sum 0x01F200
Number of opaque link LSA 0. Checksume Sum 0x00000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
A.
It is configured and functioning correctly as an OSPF internal router.
B.
It is configured and functioning correctly as an ABR attached to stub area 4.
C.
It is configured and functioning correctly as an ASBR attached to external area 4.
D.
It is configured and functioning correctly as an ABR attached to totally stubby area 4.
E.
It is not configured correctly to function as specified.
Explanation:
From the output of the “show ip ospf” command we notice 2 lines:
+ It is an area border router
+ It is a stub area, no summary LSA in this area (in Area 4)
Therefore we can conclude RouterC is an ABR and it is attached to a totally stubby area
(with no summary LSA advertised)