Juniper View Routes to a Particular Prefix

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Juniper View Routes to a Particular Prefix

You need to check to make sure the local router has a route to another router in the network.

Use the following version of the show route command:

source@Router> show route 10.0.8.1
inet.0: 18 destinations, 18 routes (18 active, 0 holddown, 0 hidden)
+ = Active Route, – = Last Active, * = Both
10.0.8.0/24        *[IS-IS/18] 00:11:18, metric 20

                    > to 10.0.0.2 via fe-1/0/1.0

For more information about the route, use the detail option:

source@Router> show route 10.0.8.1 detail
inet.0: 18 destinations, 18 routes (18 active, 0 holddown, 0 hidden)
10.0.8.0/24 (1 entry, 1 announced)
        *IS-IS Preference: 18
               Level: 2
               Next-hop reference count: 4
               Next hop: 10.0.0.2 via fe-1/0/1.0, selected
               State: <Active Int>
               Age: 11:41      Metric: 20
               Task: IS-IS
               Announcement bits (1): 0-KRT

               AS path: I

The output is straightforward because there is only one route to the destination and it is active. Some routes have multiple next hops:

source@Router> show route protocol 10.0.2.0/24
inet.0: 18 destinations, 18
routes (18 active, 0 holddown, 0 hidden)
+ = Active Route, – = Last Active, * = Both
10.0.2.0/24        *[IS-IS/18] 00:45:17, metric 20
                    > to 10.0.1.1 via fe-0/0/1.0
                      to 10.0.0.2 via fe-1/0/1.0

Routes can also be learned from multiple routing protocols:

source@Router> show route 10.1.1.0/24
inet.0: 28 destinations, 48 routes (28 active, 0 holddown, 0 hidden)
Restart Complete
+ = Active Route, – = Last Active, * = Both
10.1.1.0/24       *[OSPF/10] 00:16:20, metric 65
                      via so-0/2/0.0
                    > via so-0/2/1.0
                   [IS-IS/18] 00:16:08, metric 126
                      to 10.1.2.1 via so-0/2/0.0
                    > to 10.1.6.1 via so-0/2/1.0

Here, both OSPF and IS-IS have learned routes to 10.1.1.0/24. The OSPF routes are chosen over the IS-IS ones because of the lower preference value (10 versus 18). The two routes learned by each protocol are both equal-cost paths to the destination, so the JUNOS software randomly chooses one of them.

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