Switch virtual interface SVI configuration on gns3







A switch virtual interface (SVI) is a VLAN of switch ports represented by one interface to a routing or bridging system. There is no physical interface for the VLAN and the SVI provides the Layer 3 processing for packets from all switch ports associated with the VLAN.

How Switch virtual interface SVI  works:

This is much simpler than inter VLAN, but disadvantage is high cost of a layer-3 switch.
In SVI configuration we need a layer-3 switch, I use a 3640 router IOS and use the NM-16ESW module for layer-3 switching. The topology I used for switch virtual interface (SVI) is consist of one switch and two hosts one of them is in VLAN 10 and other is in VLAN 20. I have create two switch virtual interface s(SVI) on switch for VLAN 10 and 20, which are responsible for communicating these two VLANs.

 
Configuration for Switch:
SW#vlan database
SW(vlan)#vlan 10 name office1
SW(vlan)#vlan 20 name office2
SW(vlan)#exit
SW(config-if)#interface vlan 10
SW(config-if)#ip address 10.1.1.1 255.255.255.0
SW(config-if)#no shu
SW(config-if)#interface vlan 20
SW(config-if)#ip address 20.1.1.1 255.255.255.0
SW(config-if)#exit
SW(config)#ip routing
SW(config-if)#interface f0/0
SW(config-if)#no shutdown
SW(config-if)# switchport mode access
SW(config-if)# switchport access vlan 10
SW(config-if)#interface f0/1
SW(config-if)#no shutdown
SW(config-if)#switchport mode access
SW(config-if)# switchport access vlan 20

Configuration for Qemu1
tc@box:$ sudo su 
root@box:$ Ifconfig eth0 10.1.1.2 netmask 255.255.255.0
root@box:$ Route add default gw 10.1.1.1 eth0

Configuration for Qemu2
tc@box:$ sudo su 
root@box:$ Ifconfig eth0 20.1.1.2 netmask 255.255.255.0
root@box:$ Route add default gw 20.1.1.1 eth0

Results:
Ping from qemu1 to qemu2 is successful and voice versa.



Thanks.