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Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter22 Configuring Layer 3 Inter faces
Configuration Guidelines
Configuration Guidelines
A Catalyst 4500 series switch supports AppleTalk routing and IPX routing. For AppleTalk routing and
IPX routing information, refer to “Configuring AppleTalk” and “Configuring Novell IPX” in the
Cisco IOS AppleTalk and Novell IPX Configuration Guide at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/atipx_c/index.htm
A Catalyst 4500 series switch does not support subinterfaces or the encapsulation keyword on Layer 3
Fast Ethernet or Gigabit Ethernet interfaces.
Note As with any Layer 3 interface running Cisco IOS software, the IP address and network assigned to an
SVI cannot overlap those assigned to any other Layer 3 interface on the switch.
Configuring Logical Layer 3 VLAN Interfaces
Note Before you can configure logical Layer 3 VLAN interfaces, you must creat e and configure the VLANs
on the switch, assign VLAN membership to the Layer 2 interfaces, enable IP routing if IP routing is
disabled, and specify an IP routing protocol.
To configure logical Layer 3 VLAN interfaces, perform this task:
This example shows how to configure the logical Layer 3 VLAN interface vlan 2 and assign an IP
address:
Switch> enable
Switch# config term
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# vlan 2
Switch(config)# interface vlan 2
Switch(config-if)# ip address 10.1.1.1 255.255.255.248
Switch(config-if)# no shutdown
Switch(config-if)# end
Command Purpose
Step1 Switch(config)# vlan
vlan_ID
Creates the VLAN.
Step2 Switch(config)# interface vlan
vlan_ID
Selects an interface to configure.
Step3 Switch(config-if)# ip address ip_address
subnet_mask
Configures the IP address and IP subnet.
Step4 Switch(config-if)# no shutdown Enables the interface.
Step5 Switch(config-if)# end Exits configuration mode.
Step6 Switch# copy running-config startup-config Saves your configuration changes to NVRAM.
Step7 Switch# show interfaces [
type slot/interface
]
Switch# show ip interfaces [
type slot/interface
]
Switch# show running-config interfaces [
type
slot/interface
]
Switch# show running-config interfaces vlan vlan_ID
Verifies the configuration.