What is the primary distinction between active and passive destinations in an EIGRP topology table?

The primary distinction between active and passive destinations in an EIGRP topology table relates to the state of the routes being tracked. When a destination is in a passive state, it signifies that EIGRP has successfully learned about the destination and the routes for it are considered stable and valid. This means that the routes are trusted and can be used for routing packets without any additional processing.

In contrast, when a destination is in an active state, it indicates that EIGRP is actively seeking a route to the destination due to a failed route or an outage. Active destinations are those that are currently being queried in order to find alternative paths, and EIGRP may be waiting for responses from neighbors to determine if a new viable route can be established. This state is inherently less stable because the routing information is subject to change based on the results of ongoing queries.

Understanding this distinction is crucial for network engineers managing EIGRP, as it enables them to interpret and troubleshoot the EIGRP topology table effectively. Passive destinations are those that the protocol has confirmed to be reachable and therefore can be trusted for routing decisions, which is why they are considered more stable than active ones.