Switch Virtual Interfaces

What is Switch Virtual Interfaces?

Inter VLAN Routing, in other words Routing between VLANs can be achieved by SVIs (Switch Virtual Interfaces). Here, we need to have a Multi Layer Switch. Layer 2 switches can also have SVI, but only one.This is the default switch management SVI created for VLAN 1.

For Inter VLAN Routing, firstly, we need to use “ip routing” command on the multi layer switch that our VLANs reside. After this command, we can create a Switch Virtual Interface for each VLAN on the switch and we can assign an IP address to this SVI (Switch Virtual Interfaces). Then, At the multi layer switch, routing will be done and the communication between these VLANs will be provided.

Switch Virtual Intrefaces (SVI) Operation

For Switch Virtual Interface (SVI) Operation, think about the below figure.

Here, a PC from VLAN 2 will communicate with a PC from VLAN 4. The communication steps for this SVI Operation will be like below:

1. Traffic comes from VLAN 2
2. Traffic reaches to the SVI of VLAN 2
3. Multi Layer Switch routes the traffic
4. Traffic come to the SVI of VLAN 4
5. Traffic reaches VLAN 4

SVI Configuration Steps

Now, let’s talk about the configuration steps of Switch Virtual Interfaces: