Which of the following OSPF neighbor adjacency states is applicable only to manually configured OSPF neighbors in a Non Broadcast Multi-Access network?
Which of the following OSPF neighbor adjacency states is applicable only to manually configured OSPF neighbors in a Non Broadcast Multi-Access network?
In a Non-Broadcast Multi-Access (NBMA) network, such as Frame Relay or X.25, the OSPF neighbor adjacency state 'Attempt' is specifically used for neighbors that are manually configured. In this state, OSPF sends unicast hello packets at regular intervals to attempt to establish communication with a neighbor from which it has not received hello packets within a certain time frame. This differs from other states like Init or 2-Way, which are used in the process of establishing or maintaining neighbors in more dynamic situations.
https://www.computernetworkingnotes.com/ccna-study-guide/ospf-neighbor-states-explained-with-example.html#:~:text=In%20Non-broadcast%20multi-access%20environment%20such%20as%20Frame%20Relay,it%20does%20not%20have%20to%20discover%20them%20dynamically. Attempt ----------- In Non-broadcast multi-access environment such as Frame Relay and X.25, OSPF uses Attempt state instead of Init state. OSPF uses this state only if neighbors are statically configured with neighbor command. In this situation, it does not have to discover them dynamically. As it already knows the neighbors, it will use unicast instead of multicast in this state. Once neighborship is built, OSPF uses hello packets as keep alive. If a router does not receive a hello packet from any particular neighbor in dead interval, it will change its state to down from full. After changing the state it will make an effort to contact the neighbor by sending Hello packets. This effort is made in Attempt state. Basically Both Init and Attempt states describe similar situation where one router has sent a hello packet and waiting for response.
A correct: This state is only valid for manually configured neighbors in an NBMA environment. In Attempt state, the router sends unicast hello packets every poll interval to the neighbor, from which hellos have not been received within the dead interval. https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13685-13.html#anc14
A is corerct