OSPF (Open Shortest Path First)

Question 1

What is OSPF in Junos OS?

Answer 1

OSPF (Open Shortest Path First) is a link-state dynamic routing protocol used to find the best path for routing IP packets within a local network or autonomous system.

Question 2

How do you configure OSPF in Junos OS?

Answer 2

OSPF is configured under the protocols hierarchy, for example: set protocols ospf area <area-id>.</area-id>

Question 3

What is the purpose of OSPF areas?

Answer 3

OSPF areas are used to optimize routing by breaking a large OSPF network into smaller, more manageable sections, reducing routing overhead.

Question 4

How do you configure OSPF to advertise a network in Junos OS?

Answer 4

To advertise a network in OSPF, use the command: set protocols ospf area <area-id> interface <interface-name>.</interface-name></area-id>

Question 5

What command can be used to verify OSPF neighbor relationships in Junos OS?

Answer 5

Use the command show ospf neighbor to view the status of OSPF neighbor relationships.

Question 6

What is the OSPF router ID, and how is it configured?

Answer 6

The OSPF router ID uniquely identifies a router in OSPF. It can be configured using set protocols ospf router-id <router-id>.</router-id>

Question 7

What type of network is used in OSPF to connect routers?

Answer 7

OSPF supports various network types, such as broadcast, point-to-point, and non-broadcast multi-access (NBMA).

Question 8

What are OSPF LSAs (Link-State Advertisements)?

Answer 8

LSAs are used by OSPF to exchange routing information between routers within an area, allowing routers to build a consistent view of the network topology.

Question 9

How does OSPF prevent routing loops?

Answer 9

OSPF prevents routing loops by using a link-state database and SPF (Shortest Path First) algorithm to calculate the best path based on network topology.

Question 10

How can you view OSPF routing information in Junos OS?

Answer 10

Use the command show route protocol ospf to view OSPF routes in the routing table.