interface FastEthernet0/1
switchport access vlan 10
switchport mode access

interface FastEthernet0/2
switchport access vlan 20
switchport mode access

interface FastEthernet0/3
switchport access vlan 20
switchport mode access

interface FastEthernet0/4
switchport access vlan 30
switchport mode access

interface FastEthernet0/24
switchport trunk allowed vlan 10,20,30
switchport mode trunk

interface Vlan1
no ip address
shutdown