Edge-Core ECS4510-28P User Manual page 672

| Unicast Routing
C 19
HAPTER
Configuring the Routing Information Protocol
RIP Default Metric – Sets the default metric assigned to external
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routes imported from other protocols. (Range: 1-15; Default: 1)
The default metric must be used to resolve the problem of
redistributing external routes with incompatible metrics.
It is advisable to use a low metric when redistributing routes from
another protocol into RIP. Using a high metric limits the usefulness of
external routes redistributed into RIP. For example, if a metric of 10 is
defined for redistributed routes, these routes can only be advertised to
routers up to 5 hops away, at which point the metric exceeds the
maximum hop count of 15. By defining a low metric of 1, traffic can
follow a imported route the maximum number of hops allowed within a
RIP domain. However, note that using a low metric can increase the
possibility of routing loops. For example, this can occur if there are
multiple redistribution points and the router learns about the same
external network with a better metric from a redistribution point other
than that derived from the original source.
The default metric does not override the metric value set in the
Redistribute screen (see
page 679). When a metric value has not been configured in the
Redistribute screen, the default metric sets the metric value to be used
for all imported external routes.
RIP Max Prefix – Sets the maximum number of RIP routes which can
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be installed in the routing table. (Range: 1-7168; Default: 7168)
Default Information Originate – Generates a default external route
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into the local RIP autonomous system. (Default: Disabled)
A default route is set for every Layer 3 interface where RIP is enabled.
The response packet to external queries marks each active RIP
interface as a default router with the IP address 0.0.0.0.
Default Distance – Defines an administrative distance for external
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routes learned from other routing protocols. External routes are routes
for which the best path is learned from a neighbor external to the local
RIP autonomous system. Routes with a distance of 255 are not installed
in the routing table. (Range: 1-255; Default: 120)
Administrative distance is used by the routers to select the preferred
path when there are two or more different routes to the same
destination from two different routing protocols. A smaller
administrative distance indicates a more reliable protocol.
Use the Routing Protocol > RIP > Distance page (see
configure the distance to a specific network address, or to configure an
access list that filters networks according to the IP address of the
router supplying the routing information.
Number of Route Changes – The number of route changes made to
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the IP route database by RIP.
Number of Queries – The number of responses sent to RIP queries
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from other systems.
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"Configuring Route Redistribution" on
page 681) to