Implementing Cisco Enterprise Advanced Routing and Services (ENARSI) Practice Mode

Community Discussion

Written by other learners. Comments can disagree with the marked answer — check the official documentation when in doubt.

• 1

  I ran this through AI as I was also having trouble figuring out the ExStart vs 2-Way issue. I think it came up with a good roll up of why the given answer is correct. Basically, the given ExStart answer is more correct, all the other answers are very accurate, and the given 2-way answer has ambiguous phrasing, but I will say "multiaccess" is a dead give away for 2-way. Description Website Answer Protocol Accuracy Compare DBD packets Exchange ✅ Accurate Exchange info in multiaccess 2-Way ⚠️ Ambiguous phrasing Request missing entries Loading ✅ Accurate DR/BDR already elected ExStart ✅ Accurate (based on phrasing) Router ID not in Hello Init ✅ Accurate No Hellos received Down ✅ Accurate

• 2

  Given Answer is correct: Down: This is the first OSPF neighbor state. It means that no information (hellos) has been received from this neighbo Init This state specifies that the router has received a hello packet from its neighbor, but the receiving router ID was not included in the hello packet 2-way On broadcast media and non-broadcast multi-access networks, a router becomes full only with the designated router (DR) and the backup designated router (BDR); it stays in the 2-way state with all other neighbors Exstart Once the DR and BDR are elected, the actual process of the exchange link state information can start between the routers and their DR and BDR. Exchange In the exchange state, OSPF routers exchange database descriptor (DBD) packets Loading routers send link-state request packets. Link: https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13685-13.html

• 2

  Down:No hellos have been received from a neighbor router. init: The OSPF router ID of the receiving router was not contained in the hello message 2 way: Routers exchange information with other routers in the multiaccess network Exchange:Each router compares the DBD packets that were received from the other router ExStart:The network has already elected a DR and a backup BDR Loading:The neighboring router requests the other routers to send missing entries