Examkin

Soru

Zorluk: KolayOSPFv2 Neighbor Adjacencies and Router ID

Two directly connected Cisco routers are configured to run OSPFv2 on their connecting GigabitEthernet interfaces. Interface GigabitEthernet0/0 on Router A is placed in OSPF Area 0, while interface GigabitEthernet0/0 on Router B is placed in OSPF Area 1. Which statement correctly describes the result of this configuration?

  1. The routers will fail to form an OSPF neighbor adjacency.Cevap
  2. B
    The routers will establish a neighbor relationship but will refuse to exchange routing updates.
  3. C
    The routers will form an adjacency only if their OSPF process IDs match.
  4. D
    The router with the higher Router ID will automatically adjust its area to match the peer router.

Cevap

The routers will fail to form an OSPF neighbor adjacency.
For two OSPFv2 routers to establish a neighbor adjacency, key fields in their Hello packets must match. These mandatory matching parameters include the Area ID, Subnet Mask, Hello and Dead intervals, and Authentication fields. Because Router A is configured in Area 0 and Router B is configured in Area 1 on the connecting segment, the routers will discard each other's Hello packets and fail to form an adjacency.

Adım Adım Çözüm

1
Identify the OSPF neighbor requirements for directly connected interfaces.
Neighbor adjacencies require identical Hello/Dead timers, Area ID, Subnet Mask, and MTU settings in Hello packets.
OSPF validation rules state that any mismatch in essential Hello packet fields will cause the router to drop incoming Hello packets.
2
Compare the configured OSPF Area IDs of Router A and Router B.
Router A is in Area 0 and Router B is in Area 1.
Because the Area IDs differ, Hello packet validation fails upon receipt.
3
Determine the resulting neighbor state.
No neighbor adjacency is formed and the routers remain in the Down state.
Without matching parameters, OSPF neighbor relationship negotiation cannot proceed.

Anahtar Kavram

OSPFv2 Neighbor Adjacency Requirements
Tahmini Süre:45s
Bu soruyu puanla

Konular

OSPFv2 Neighbor Adjacencies and Router ID

Bu konudan daha fazla soru