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Which type of route is shown in the following output?

Which type of route is shown in the following output?

user@router> show route 0/0 exact

inet.0: 18 destinations, 18 routes (18 active, 0 holddown, 0 hidden) + = Active Route, – = Last Active, * = Both

0.0.0.0/0 *[Aggregate/130] 03:03:43
> to 10.0.0.6 via ge-0/0/0.102

PrepAway - Latest Free Exam Questions & Answers

A.
generate

B.
aggregate

C.
static

D.
floating static

Explanation:
A generate route can send traffic over a next hop that is a contribtuing route, aggregate route cant. If you define an aggregate route and if the next hop is a contributing route to the aggregate route than the route would be a hidden route. If you need to summarize the 10.100.0.0 network and the next hop is on the 10 network than you could use the generate route to advertise the summary route, the aggregate route would not work in the case.

Generated Routes
Generated routes are similar in nature and configuration to aggregate routes. Like aggregate routes, generated routes become active in the routing table when at least one contributing route (more specific route) for the generated route is also active in the routing table. The output of show route commands displays generated routes as aggregate routes, as shown in the following sample output:

user@R1> show route 0/0 exact detail
inet.0: 14 destinations, 14 routes (14 active, 0 holddown, 0 hidden)
0.0.0.0/0 (1 entry, 1 announced)
*Aggregate Preference: 130
Next hop type: Router, Next hop index: 546
Next-hop reference count: 4
Next hop: 172.30.25.1 via ge-0/0/1.100, selected
State: <Active Int Ext>
Local AS: 65400
Age: 1:03:46
Task: Aggregate
Announcement bits (2): 0-KRT 2-OSPF
AS path: I
Flags: Generate Depth: 0 Active
Contributing Routes (1):
10.0.0.0/16 proto BGP

Unlike aggregate routes, the next hop associated with a generated route is the same next hop as that of the primary contributing route. The primary contributing route is the route with lowest route preference that falls within the aggregated range of prefixes. If there are multiple routes that fall within the aggregated range that share the same route preference, the route with the lowest number prefix, not the lowest prefix length, is selected as the primary contributing route.

For a route to qualify as a contributing route for a generated route, the route must have a valid forwarding next hop other than the local device; otherwise the generated route becomes hidden, as shown in the following sample output:

user@R1> show route hidden

inet.0: 7 destinations, 7 routes (6 active, 0 holddown, 1 hidden)
+ = Active Route, – = Last Active, * = Both
0.0.0.0/0 [Aggregate] 00:17:30
Reject
A generated route is often referred to as a route of last resort. This reference is because of one of the possible uses of generated routes, which is to source a default route when specific conditions are met. You can define the required conditions through routing policy. We show an example of how to use routing policy to define the required conditions for a generated route later in this section.


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