Your company's network consist of a CORE module running OSPF Area 0 and multiple buildings with 2x distribution switches per building running OSPF NSSA areas.

You have asked your junior network administrator to configure OSPFv3 (for IPv6) to match the same design as OSPFv2 (for IPv4) in building 1 as per below diagram. The design requires that both COREs will inject a default route into the NSSA area, so each DIST will have 2 paths for default route.

After he finishes the configuration, your junior colleague realizes that there are default routes 0.0.0.0 for IPv4 (received from COREs) but there is no default ::/0 for IPv6.

quiz-5

You perform various troubleshooting, including the commands below: 

Dist-2#sh ipv6 osp int br
Interface    PID   Area            Intf ID    Cost  State Nbrs F/C
Vl102        1     0.0.0.0         30         1     DR    0/0
Lo0          1     192.168.1.0     27         1     LOOP  0/0
Vl201        1     192.168.1.0     35         1     DR    0/0
Vl200        1     192.168.1.0     34         1     DR    0/0
Vl105        1     192.168.1.0     33         1     DR    0/0
Vl104        1     192.168.1.0     32         1     DR    0/0
Vl103        1     192.168.1.0     31         1     DR    0/0
Vl101        1     192.168.1.0     29         1     DR    0/0
Vl100        1     192.168.1.0     28         1     DR    0/0
Fa0/1        1     192.168.1.0     5          1     DR    1/1
Fa0/0        1     192.168.1.0     4          1     DR    1/1
Dist-2#
Dist-2#sh ipv6 osp nei

Neighbor ID     Pri   State           Dead Time   Interface ID    Interface
192.168.255.2     1   FULL/BDR        00:00:36    6               FastEthernet0/1
192.168.255.1     1   FULL/BDR        00:00:37    6               FastEthernet0/0
Dist-2#

Is there a problem with the design or your junior colleague did a mistake with the implementation ? What is the problem?

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