Switch Virtual Interfaces - Cisco Catalyst 3750-X Software Configuration Manual

Chapter 13 Configuring Interface Characteristics
The number of routed ports that you can configure is not limited by software. However, the
interrelationship between this number and the number of other features being configured might impact
CPU performance because of hardware limitations. See the
page 13-37
For more information about IP unicast and multicast routing and routing protocols, see
"Configuring IP Unicast Routing"
The IP base feature set supports static routing and the Routing Information Protocol (RIP). For full
Note
Layer 3 routing or for fallback bridging, you must enable the IP services feature set on the standalone
switch, or the stack master.

Switch Virtual Interfaces

A switch virtual interface (SVI) represents a VLAN of switch ports as one interface to the routing or
bridging function in the system. Only one SVI can be associated with a VLAN, but you need to configure
an SVI for a VLAN only when you wish to route between VLANs, to fallback-bridge nonroutable
protocols between VLANs, or to provide IP host connectivity to the switch. By default, an SVI is created
for the default VLAN (VLAN 1) to permit remote switch administration. Additional SVIs must be
explicitly configured.
You cannot delete interface VLAN 1.
Note
SVIs provide IP host connectivity only to the system; in Layer 3 mode, you can configure routing across
SVIs.
Layer 3 mode is not supported on switches running the LAN base feature set.
Note
Although the switch stack or switch supports a total of 1005 VLANs (and SVIs), the interrelationship
between the number of SVIs and routed ports and the number of other features being configured might
impact CPU performance because of hardware limitations. See the
section on page 13-37
reached.
SVIs are created the first time that you enter the vlan interface configuration command for a VLAN
interface. The VLAN corresponds to the VLAN tag associated with data frames on an ISL or
IEEE 802.1Q encapsulated trunk or the VLAN ID configured for an access port. Configure a VLAN
interface for each VLAN for which you want to route traffic, and assign it an IP address. For more
information, see the
When you create an SVI, it does not become active until it is associated with a physical port.
Note
SVIs support routing protocols and bridging configurations. For more information about configuring IP
routing, see
Routing,"and
OL-21521-01
for information about what happens when hardware resource limitations are reached.
and
for information about what happens when hardware resource limitations are
"Manually Assigning IP Information" section on page
Chapter 42, "Configuring IP Unicast Routing," Chapter 48, "Configuring IP Multicast
Chapter 50, "Configuring Fallback Bridging."
"Configuring Layer 3 Interfaces" section on
Chapter 48, "Configuring IP Multicast Routing."
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
Interface Types
Chapter 42,
"Configuring Layer 3 Interfaces"
3-15.
13-5