Dell S3048-ON, Configuration Manual

Page: 675 / 1036

Generating a Default Route
Traffic is forwarded to the default route when the traffic’s network is not explicitly listed in the routing table.
Default routes are not enabled in RIP unless specified. Use the
default-information originate
command in ROUTER RIP mode
to generate a default route into RIP. In Dell Networking OS, default routes received in RIP updates from other routes are advertised if you
configure the
default-information originate
command.
• Specify the generation of a default route in RIP.
ROUTER RIP mode
default-information originate [always] [metric value ] [route-map route-map-name ]
•
always
: Enter the keyword
always
to always generate a default route.
•
value
The range is from 1 to 16.
•
route-map-name
: The name of a configured route map.
To confirm that the default route configuration is completed, use the
show config
command in ROUTER RIP mode.
Summarize Routes
Routes in the RIPv2 routing table are summarized by default, thus reducing the size of the routing table and improving routing efficiency in
large networks.
By default, the
autosummary
command in ROUTER RIP mode is enabled and summarizes RIP routes up to the classful network
boundary.
If you must perform routing between discontiguous subnets, disable automatic summarization. With automatic route summarization
disabled, subnets are advertised.
The
autosummary
command requires no other configuration commands. To disable automatic route summarization, enter
no
autosummary
in ROUTER RIP mode.
NOTE: If you enable the
ip split-horizon
command on an interface, the system does not advertise the summarized
address.
Controlling Route Metrics
As a distance-vector protocol, RIP uses hop counts to determine the best route, but sometimes the shortest hop count is a route over the
lowest-speed link.
To manipulate RIP routes so that the routing protocol prefers a different route, manipulate the route by using the
offset
command.
Exercise caution when applying an
offset
command to routers on a broadcast network, as the router using the
offset
command is
modifying RIP advertisements before sending out those advertisements.
The
distance
command also allows you to manipulate route metrics. To assign different weights to routes so that the ones with the
lower weight or administrative distance assigned are preferred, use the
distance
command.
To set route matrixes, use the following commands.
• Apply a weight to all routes or a specific route and ACL.
ROUTER RIP mode
distance weight [ ip-address mask [ access-list-name ]]
Configure the following parameters:
Routing Information Protocol (RIP) 675