Cisco Systems 3560X Manual De Usuario
42-92
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 42 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 build a route to a
particular destination and are useful for specifying a gateway of last resort to which all unroutable
packets are sent.
destination to take a specified path. Static routes can be important if the router cannot 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.
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
dynamic routing information by assigning administrative distance values. Each dynamic routing
protocol has a default administrative distance, as listed in
. 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.
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 in the routing table to be connected 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.
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 in the routing table to be connected 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 current state of the routing table to verify
the configuration.
the configuration.
Step 5
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Table 42-16
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