Default change dns kitkat

root@:/ # ndc resolver flushif -- flushes old DNS servers
root@:/ # ndc resolver flushdefaultif -- flush resolver
root@:/ # ndc resolver setifdns <iface> <domains> <dns1> <dns2> ... -- Add the new servers
root@:/ # ndc resolver setdefaultif -- Set as the default device

What should I replace instead of iface and domains?

Using the ifconfig command outputs are various interfaces and in particular:

to set the dns to google to use when mobile connection, okay this command?

root@:/ # ndc resolver setifdns rmnet0 w w w .google.c o m -- (I had to write the domains that otherwise would not let me reply, of course, I wrote all attached)
root@:/ # ndc resolver setdefaultif --

When I give the command

root@:/ # ndc resolver flushif --

the system responds with:
500 0 wrong number of arguments to resolver setdefaultif

While when I give other commands responds with:

200 0 Resolver command succeded

I apologize for the bad english but i used a translator