Configuring Vlans As Layer 3 Interfaces - Cisco Catalyst 4500 series Administration Manual

Chapter 34 Configuring Layer 3 Interfaces
5 minute output rate 0 bits/sec, 0 packets/sec
Switch#
This example shows how to use the show running-config command to display the interface IP address
configuration of Layer 3 VLAN interface VLAN 2:
Switch# show running-config
Building configuration...
Current configuration : !
interface Vlan2
ip address 10.1.1.1 255.255.255.248
!
ip classless
no ip http server
!
!line con 0
line aux 0
line vty 0 4
!
end

Configuring VLANs as Layer 3 Interfaces

This section consists of the following subsections:
•
•
•
Configuring SVI Autostate Exclude
The SVI Autostate Exclude feature is enabled by default and is synchronized with the STP state.
Note
The SVI Autostate Exclude feature shuts down (or brings up) the Layer 3 interfaces of a switch when
the following port configuration changes occur:
•
•
SVI Autostate Exclude enables you to exclude the access ports and trunks in defining the status of the
SVI (up or down) even if it belongs to the same VLAN. If the excluded access port and trunk is in up
state and other ports are in down state in the VLAN, the SVI state is changed to down.
To make the SVI state up, at least one port in the VLAN should be up and not excluded. This action helps
to exclude the monitoring port status when you are determining the status of the SVI.
OL_28731-01
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
Configuring SVI Autostate Exclude, page 34-7
Configuring IP MTU Sizes, page 34-9
Configuring Layer 3 Interface Counters, page 34-10
When the last port on a VLAN goes down, the Layer 3 interface on that VLAN is shut down
(SVI- autostated).
When the first port on the VLAN is brought back up, the Layer 3 interface on the VLAN that was
previously shut down is brought up.
Software Configuration Guide—Release IOS XE 3.6.0E and IOS 15.2(2)E
Configuring VLANs as Layer 3 Interfaces
34-7