Configuring static unicast routes – Dell POWEREDGE M1000E User Manual

Page 986

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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide

OL-13270-03

Chapter 38 Configuring IP Unicast Routing

Configuring Protocol-Independent Features

Configuring Static Unicast Routes

Static unicast routes are user-defined routes that cause packets moving between a source and a
destination to take a specified path. Static routes can be important if the router cannot dynamically build
a route to a particular destination and are useful for specifying a gateway of last resort to which all
unroutable packets are sent.

Beginning in privileged EXEC mode, follow these steps to configure a static route:

Use the no ip route prefix mask {address | interface} global configuration command to remove a static
route.

The switch retains static routes until you remove them. However, you can override static routes with
dynamic routing information by assigning administrative distance values. Each dynamic routing
protocol has a default administrative distance, as listed in

Table 38-16

. If you want a static route to be

overridden by information from a dynamic routing protocol, set the administrative distance of the static
route higher than that of the dynamic protocol.

Static routes that point to an interface are advertised through RIP, IGRP, and other dynamic routing
protocols, whether or not static redistribute router configuration commands were specified for those
routing protocols. These static routes are advertised because static routes that point to an interface are
considered as connected in the routing table and hence lose their static nature. However, if you define a
static route to an interface that is not one of the networks defined in a network command, no dynamic
routing protocols advertise the route unless a redistribute static command is specified for these
protocols.

Command

Purpose

Step 1

configure terminal

Enter global configuration mode.

Step 2

ip route prefix mask {address | interface} [distance]

Establish a static route.

Step 3

end

Return to privileged EXEC mode.

Step 4

show ip route

Display the routing table to verify the configuration.

Step 5

copy running-config startup-config

(Optional) Save your entries in the configuration file.

Table 38-16

Dynamic Routing Protocol Default Administrative Distances

Route Source

Default Distance

Connected interface

0

Static route

1

Enhanced IRGP summary route

5

External BGP

20

Internal Enhanced IGRP

90

IGRP

100

OSPF

110

Internal BGP

200

Unknown

225

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