OSPF Configuration Flashcards
7 cards from real ICND1 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 OSPF Configuration flashcards as text
Which command sets the OSPF reference bandwidth to 1000 Mbps to correctly calculate costs for Gigabit interfaces?
Answer: auto-cost reference-bandwidth 1000
'auto-cost reference-bandwidth 1000' under the OSPF process sets the reference to 1000 Mbps, giving GigE interfaces a cost of 1.
What is the multicast address used by OSPF Designated Routers and Backup Designated Routers?
Answer: 224.0.0.6
224.0.0.6 is the AllDRouters multicast address used to send updates specifically to the DR and BDR.
A network engineer needs to advertise a default route into OSPF. Which command accomplishes this?
Answer: default-information originate
'default-information originate' under the OSPF process redistributes a default route into the OSPF domain.
Which OSPF neighbor state indicates that routers have exchanged DBD packets and are now requesting missing LSAs?
Answer: Loading
In the Loading state, routers send LSR packets to request specific LSAs that were identified as missing during Exchange.
What is the effect of configuring 'ip ospf priority 0' on an interface?
Answer: The router is ineligible to become the DR or BDR
An OSPF priority of 0 makes the router ineligible to become either the Designated Router or Backup Designated Router.
Which command verifies that OSPF is enabled on a specific interface and shows its cost?
Answer: show ip ospf interface brief
'show ip ospf interface brief' lists all OSPF-enabled interfaces with their area, IP, cost, state, and neighbor counts.
OSPF uses which algorithm to calculate the shortest path to each destination?
Answer: Dijkstra's Shortest Path First (SPF)
OSPF uses Dijkstra's SPF algorithm to compute loop-free shortest paths based on cumulative link costs.