interface GigabitEthernet0/0
!
interface GigabitEthernet2
 switchport access vlan 30
!
interface GigabitEthernet3
 switchport trunk encapsulation dot1q
 switchport mode trunk
 switchport trunk native vlan 20
 switchport trunk allowed vlan 15-20,40
 switchport trunk pruning vlan 10,20
!
