dhcp6c for prefix delegation

dhcp6c.conf

interface pppoe0 {
  send ia-pd 1;                                                                                   	
};

id-assoc pd 1 {                                                                                         	
  prefix-interface vr1 {                                                                          	
    sla-id 0;                                                                               	
    sla-len 16;                                                                             	
  };                                                                                              	
};