option RFC-3442-classless-static-routes code 121=array of unsigned integer 8;

subnet 192.168.10.0 netmask 255.255.255.0 
{
    range 192.168.10.20 192.168.10.40;
    option routers 192.168.10.254;
    default-lease-time 600;
    max-lease-time 7200;
    option RFC-3442-classless-static-routes 24,172,16,2,192,168,10,254, 0,192,168,10,253;
}

host GW 
{
    hardware ethernet 42:00:aa:00:00:03;
}

subnet 172.16.2.0 netmask 255.255.255.0 
{
    range 172.16.2.1 172.16.2.254;
    option routers 172.16.2.254;
    option broadcast-address 172.16.2.255;
    default-lease-time 600;
    max-lease-time 7200;
}