Asante Technologies 35516 Set Metrics for Redistributed Routes, Set Administrative Distance

Models: 35516

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Router(config)# route-map

map-tag permit 10

Router(config-route-map)#

?

end

End current mode and change to enable mode.

exit

Exit current mode and down to previous mode

help

Description of the interactive help system

match

Match values from routing table

no

Negate a command or set its defaults

on-match

Exit policy on matches

quit

Exit current mode and down to previous mode

route-map

Create route-map or enter route-map command mode

set

Set values in destination routing protocol

Router(config-route-map)#

One or more match and set commands typically follow a route-mapcommand. If there are no match commands, then everything matches. If there are no set commands, nothing is done. Therefore, you need at least one match or set command. You can enter match commands into a route map in any order. If the match criteria are met, and permit is on, then the route is redistributed or controlled as defined by the set commands and route-map processing is complete. If the match criteria are met, and deny is on, then the route is not redistributed or controlled and route-map processing is complete. To define conditions for redistributing routes from a source route entry into the RIP tables, perform at least one of the following tasks in route-map configuration mode:

Command

Purpose

match interface interface-name

Match the specified interface.

match ip address {access-list-

Match a standard access list or prefix list.

name prefix-listprefix-list-name}

 

match ip next-hop access-list-name

Match a next-hop router address passed by one of the

 

access lists specified.

match metric metric-value

Match the specified metric.

set ip next-hop ip-address

Specify the address of the next hop.

set metric metric-value

Set the metric value to give the redistributed routes.

5.4.5 Set Metrics for Redistributed Routes

The metrics of one routing protocol do not necessarily translate into the metrics of another. For example, the RIP metric is a hop count and the OSPF metric is a combination of five quantities.

In such situations, an artificial metric is assigned to the redistributed route. Because of this unavoidable tampering with dynamic information, carelessly exchanging routing information between different routing protocols can create routing loops, which can seriously degrade network operation.

To use the current routing protocol’s metric value for all redistributed routes, enter the following command in router configuration mode.

Command

Purpose

default-metric metric-value

Cause the current routing protocol to use the same metric value

 

for all redistributed routes.

Note: The metric value range is very large for compatibility with other protocols (0-2494967295).

For RIP, valid metric value is from 1 to 16.

5.4.6 Set Administrative Distance

The administrative distance is a value that rates the trustworthiness of a routing information source, such as an individual router or a group of routers. In a large network, some routing protocols and some routers can be more reliable than others as sources of routing information. Also, when multiple routing processes are running in the same router for IP, it is possible for the same route to be advertised by more than one routing

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Asante Technologies 35516 user manual Set Metrics for Redistributed Routes, Set Administrative Distance