Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 707)

Route Selection
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 28.3
RIB and FIB Routing Tables
Your device maintains its routing information in routing tables that tell your device how to
find a remote network or host. Each route is uniquely identified in a table by its IP address,
network mask, next hop, interface, protocol, and policy. There are two routing tables
populated by your device: the Routing Information Base (RIB) and the Forwarding
Information Base (FIB).
Routing
Information Base
The RIB records all the routes that your device has learned. Your device uses the RIB to
advertise routes to its neighbor devices and to populate the FIB. It adds routes to this table
when:
■ you add a static route using the ip route command
■ one or more routing protocols, such as RIP or OSPF, exchange routing information
with other routers or hosts
■ your device receives route information from a connected interface
■ your device gathers route information from an ICMP redirect message or DHCP
message
Understanding the Routing Information Base (RIB)
Use the show ipv6 route database command to view the IPv6 RIB.
Use the show ip route database command to view the IPv4 RIB.
The RIB in AlliedWare Plus displays all the routes sent to the RIB by the routing protocols,
plus all the static and connected routes.
The angle bracket > character in show output indicates which route has been selected as
the best route. The best routes are installed in the Forwarding Information Base (FIB).
Routes which have been installed in the software FIB are marked with a star * symbol in
show output.
The Administrative Distance and the Metric are seen in the square brackets with AD on the
left of the backslash and Metric to the right of AD, so this is shown as: [AD / Metric]
See the below list of other information displayed in the RIB:
■ Route type
■ Prefix and Prefix Length
■ Administrative Distance
■ Metric
■ Next-Hop
■ Exit interface
■ Uptime
Note Routes in the FIB are used locally but are not advertised to neighbors if they are
not also in the RIB.