Juniper Routes in the Forwarding Table

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Juniper Routes in the Forwarding Table

You want to see the routes that RPD has installed in the forwarding table and that the router is actually using to forward packets.
Use the show route forwarding-table command to see the active routes in the
 Routing Engine’s forwarding table:

source@RouterA> show route forwarding-table
Routing table: inet
Internet:
Destination        Type RtRef Next hop           Type Index NhRef Netif
default            user     1 0:10:db:ff:20:80   ucst   335     3 fe-0/0/0.0
default            perm     0                    rjct    14     1
10.17.214.0/26     intf     0                    rslv   329     1 fe-0/0/1.0
10.17.214.0/32     dest     0 10.17.214.0        recv   327     1 fe-0/0/1.0
10.17.214.27/32    intf     0 10.17.214.27       locl   328     2
10.17.214.27/32    dest     0 10.17.214.27       locl   328     2
10.17.214.63/32    dest     0 10.17.214.63       bcst   320     1 fe-0/0/1.0
172.19.121.0/24    intf     0                    rslv   326     1 fe-0/0/0.0
172.19.121.0/32    dest     0 172.19.121.0       recv   324     1 fe-0/0/0.0
172.19.121.1/32    dest     0 0:10:db:ff:20:80   ucst   335     3 fe-0/0/0.0
172.19.121.113/32  intf     0 172.19.121.113     locl   325     2

To see the forwarding entries that the PFE uses to forward packets, you must use the show pfe route command:

source@RouterA> show pfe route ip
IPv4 Route Table 0, default.0, 0x0:
Destination                       NH IP Addr      Type     NH ID Interface
——————————— ————— ——– —– ———
default                           172.19.121.1    Unicast   335  fe-0/0/0.0
10.17.214.0/26                                    Resolve   329  fe-0/0/1.0
10.17.214.0                       10.17.214.0     Receive   327  fe-0/0/1.0
10.17.214.27                      10.17.214.27      Local   328
10.17.214.63                                        Bcast   320  fe-0/0/1.0
172.19.121/24                                     Resolve   326  fe-0/0/0.0
172.19.121.0                      172.19.121.0    Receive   324  fe-0/0/0.0
172.19.121.1                      172.19.121.1    Unicast   335  fe-0/0/0.0
172.19.121.113                    172.19.121.113    Local   325

The show route forwarding-table output shows routes from all routing tables, so it includes IPv4, IPv6, ISO, and MPLS routes, as well as routes from the internal JUNOS routing table. The output in this recipe shows sections for each type of routing table. You can also look at just the forwarding table for one of the routing families:

source@RouterA> show route forwarding-table family ?
Possible completions:
  inet                 IP version 4 (IPv4)
  inet6                IP version 6 (IPv6)
  iso                  International Standards Organization protocol
  mpls                 Multiprotocol Label Switching
  tnp                  Trivial Network Protocol
  unix                 UNIX

Here, you see a route learned by IS-IS:

source@RouterA> show route 10.0.1.0/24
inet.0: 9 destinations, 9 routes (9 active, 0 holddown, 0 hidden)
+ = Active Route, – = Last Active, * = Both
10.0.1.0/24        *[IS-IS/15] 00:11:07, metric 20
                   > to 10.0.16.2 via fe-0/0/0.0

source@RouterA> show route forwarding-table destination 10.0.1.0/24
Routing table: inet
Internet:
Destination        Type RtRef Next hop           Type Index NhRef Netif
10.0.1.0/24        user     0 10.0.16.2          ucst   337     5 fe-0/0/0.0

A route that is unreachable is marked iddn if the interface to that destination is down.

You can also look at the entries for a particular destination:

source@RouterA> show route forwarding table destination 10.17.214.0/32
Routing table: inet
Internet:
Destination        Type RtRef Next hop           Type Index NhRef Netif
10.17.214.0/32     dest     0 10.17.214.0        recv   327     1 fe-0/0/1.0

source@RouterA> show pfe route ip prefix 10.17.214.0/32
IPv4 Route Table 0, default.0, 0x0:
Destination                       NH IP Addr      Type     NH ID Interface
——————————— ————— ——– —– ———
10.17.214.0                       10.17.214.0      Receive   327 fe-0/0/1.0

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