Cisco Systems 3750E manual Enabling IP Unicast Routing, 38-19

Chapter 38 Configuring IP Unicast Routing

Enabling IP Unicast Routing

Table 38-3	Commands to Display Caches, Tables, and Databases
Command		Purpose
show arp		Display the entries in the ARP table.
show hosts		Display the default domain name, style of lookup service, name server hosts,
		and the cached list of hostnames and addresses.
show ip aliases		Display IP addresses mapped to TCP ports (aliases).
show ip arp		Display the IP ARP cache.
show ip interface [interface-id]		Display the IP status of interfaces.
show ip irdp		Display IRDP values.
show ip masks address		Display the masks used for network addresses and the number of subnets
		using each mask.
show ip redirects		Display the address of a default gateway.
show ip route [address [mask]] [protocol]		Display the current state of the routing table.
show ip route summary		Display the current state of the routing table in summary form.

Enabling IP Unicast Routing

By default, the switch is in Layer 2 switching mode and IP routing is disabled. To use the Layer 3 capabilities of the switch, you must enable IP routing.

Beginning in privileged EXEC mode, follow these steps to enable IP routing:

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	ip routing	Enable IP routing.
Step 3
	router ip_routing_protocol	Specify an IP routing protocol. This step might include other
		commands, such as specifying the networks to route with the
		network (RIP) router configuration command. For information on
		specific protocols, see sections later in this chapter and to the Cisco
		IOS IP Configuration Guide, Release 12.2.
		Note The IP base feature set supports only RIP as a routing
		protocol.
Step 4
	end	Return to privileged EXEC mode.
Step 5
	show running-config	Verify your entries.
Step 6
	copy running-config startup-config	(Optional) Save your entries in the configuration file.

Use the no ip routing global configuration command to disable routing.

This example shows how to enable IP routing using RIP as the routing protocol:

Switch# configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Switch(config)# ip routing

Switch(config)# router rip

	Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-02		38-19