LevelOne GTL-2691 - Manual (Page 1451)

C HAPTER 49 | IP Routing Commands
Global Routing Configuration
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C OMMAND M ODE
Privileged Exec
C OMMAND U SAGE
◆ The FIB contains information required to forward IP traffic. It contains
the interface identifier and next hop information for each reachable
destination network prefix based on the IP routing table. When routing
or topology changes occur in the network, the routing table is updated,
and those changes are immediately reflected in the FIB.
The FIB is distinct from the routing table (or, Routing Information
Base), which holds all routing information received from routing peers.
The forwarding information base contains unique paths only. It does
not contain any secondary paths. A FIB entry consists of the minimum
amount of information necessary to make a forwarding decision on a
particular packet. The typical components within a forwarding
information base entry are a network prefix, a router port identifier,
and next hop information.
◆ This command only displays routes which are currently accessible for
forwarding. The router must be able to directly reach the next hop, so
the VLAN interface associated with any dynamic or static route entry
must be up. Note that routes currently not accessible for forwarding,
may still be displayed by using the show ip route database command.
E XAMPLE
In the following example, note that the entry for RIP displays both the
distance and metric for this route.
Console#show ip route
Codes: C - connected, S - static, R - RIP, B - BGP
O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default
R 10.1.1.0/24 [120/2] via 192.168.1.10, VLAN1, 00:00:14
C 127.0.0.0/8 is directly connected, lo
C 192.168.1.0/24 is directly connected, VLAN1
Console#
show ip route
database
This command displays entries in the Routing Information Base (RIB).
C OMMAND M ODE
Privileged Exec
C OMMAND U SAGE
The RIB contains all available routes learned through dynamic routing
protocols, directly attached networks, and any additionally configured
routes such as static routes. The RIB contains the set of all available routes
from which optimal entries are selected for use by the Forwarding