route add default gw mango-gw
              adds  a  default  route  (which  will  be  used  if no other route matches).  All packets using this route will be gatewayed through
              "mango-gw". The device which will actually be used for that route depends on how we can reach  "mango-gw"  -  the  static  route  to
              "mango-gw" will have to be set up before.