en
conf t

hostname L3Switch

ip routing

int g0/0
 no switchport 
 ip address 192.168.1.1 255.255.255.0
exit

!! configure g0/1 yourself with 2.1 ip

ip dhcp pool LAN1
 network 192.168.1.0 255.255.255.0
 default-router 192.168.1.1
exit

!! configure DHCP pool for LAN2 yourself
!! now start the clients and ping from 1.2 -> 2.2