System Administrator 2026 — Test 41

Correct Answer: B. B. Routing table
Explanation: The outcome of Djikstra’s calculation is the main source of entries in the routing table as it is the algorithm that is used to find the shortest path in OSPF. The calculations are done after receiving every new LSU.

Correct Answer: A. A. 89
Explanation: 89 is the IP protocol number for OSPF packets. 86 is the protocol number for DGP, 76 is the protocol number for Backroom-SATNET-Monitoring and 20 is the protocol number for Host Monitoring Protocol.

Correct Answer: D. D. Query
Explanation: LSU is the Link State Update packet, LSR is the Link State Request packet and DBD is the Database Descriptor packet in OSPF. Query packet is NOT an OSPF packet type.

Correct Answer: A. A. 224.0.0.5
Explanation: Hello protocol is used to discover neighboring routers automatically. It makes sure that the communication between neighbors is bidirectional. The multicast address that the OSPF Hello protocol uses is 224.0.0.5.

Correct Answer: A. A. True
Explanation: The Hello protocol sends periodic updates to ensure that a neighbor relationship is maintained between adjacent routers. It’s similar to the real world moral construct of saying “Hello” to initialize the communication.

Correct Answer: A. A. Exstart and exchange
Explanation: DBD stands for Database Descriptor. DBD packets are involved during the two states Exstart and Exchange. In exstart, the master and the slaves are decided and in the exchange state, the DBD is exchanged among the neighbors.

Correct Answer: D. D. 1 hour
Explanation: Each LSA has its own age timer. By default, an LSA waits for 30 minutes before requiring an update. So to make sure that each router first has an up-to-date LSA, OSPF refreshes LSAs after every 1 hour.

Correct Answer: D. D. Maxage time
Explanation: The packet length field gives the length of the packet in bits. The Authentication type field gives the type of authentication used. The router ID field gives the ID of the source router of the packet. In an OSPF packet header, there is no field called Maxage time.

Correct Answer: D. D. €?[wildcard-mask] area [area-id]€? and €?router ospf [process-id]€?
Explanation: The “Router ospf [process-id]” command enables OSPF routing protocol in the router and the “[Wildcard-mask] area [area-id]” command is used to select the interfaces that we want to include in the OSPF process. That is enough for the basic configuration of OSPF in a router.

Correct Answer: D. D. Show ip ospf neighbor
Explanation: The “Show ip ospf neighbor” command is the OSPF show command that can describe a list of OSPF adjacencies i.e. the list of adjacent nodes or neighbors. The router will only communicate with its neighbors directly.