Switching - switched virtual interface (SVI)
On a multilayer switch, also called a Layer 3 switch, it is possible to configure what is known as a Switched Virtual Interface or SVI. This is a virtual interface created on a specific VLAN and can be used as a default gateway of the subnet of that VLAN. All Layer 3 configurations, such as IPv4 address and subnet mask are configured there.
All hosts connected to an access port on the same VLAN as that SVI have direct access to that Layer 3 interface as a default gateway. The advantage here is that multiple hosts can connect to multiple access ports on that particular VLAN and have access to that default gateway.
To configure an SVI on a particular VLAN and assign it an IP address, use the following commands:
SW1(config)#interface vlan 10 SW1(config-if)#no shutdown SW1(config-if)#ip address 192.168.10.254 255.255.255.0
An alternative to using an SVI on a Layer 3 switch is to use a routed port.