Inalp Networks SmartWare Release 2.10, Руководство по настройке программного обеспечения

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156 RIP Configuration
destination-network entry, the SmartNode adds one to the metric value indicated in the update and
enters the network in the routing table. The IP address of the sender is used as the next hop.
RIP prevents routing loops from continuing indefinitely by implementing a limit on the number of
hops allowed in a path from the source to a destination. The maximum number of hops in a path is
15. If a SmartNode receives a routing update that contains a new or changed entry, and if increasing
the metric value by one causes the metric to be infinity (that is, 16), the network destination is
considered unreachable.
Because metrics cannot be directly compared, you must specify the default metric in order to
designate the cost of the redistributed route used in RIP updates. All routes that are redistributed
will use the default metric.
Setting the default route metric, which is a number, indicating the distance to the destination
network element, e.g. another router or SmartNode in a network, is possible with the
rip default-
route-value command. The value is between 1 and 15 for a valid route, or 16 for an unreachable
route.
Procedure
To set the routing metric on an interface
Mode
Interface
Command Purpose
Step 3 node (if-ip)[ name ]#rip default-
route-value value
Sets the routing metric to value indicating the
distance to the destination on interface name
Example: Specifying The Default Route Metric
The following example shows how to set the routing metric to 4 on IP interface wan on a SmartNode.
SN(cfg)# context ip router
SN(ctx-ip)[router]# interface wan
SN(if-ip)[wan]# rip default-route-value 4
18.13 Enabling RIP Split-Horizon Processing
Normally, routers that are connected to broadcast-type IP networks and that use distance-vector
routing protocols employ the
split horizon mechanism to reduce the possibility of routing loops. Split
horizon blocks information about routes from being advertised by a router out of any interface from
which that information originated. This behavior usually optimizes communications among multiple
routers, particularly when links are broken. However, with non-broadcast networks (such as Frame
Relay), situations can arise for which this behavior is less than ideal. For these situations, you might
want to disable split horizon for RIP.
Procedure
To enable split horizon on an interface
Mode
Interface
Software Configuration Guide Release 2.10, Revision 1.00