[Discuss-gnuradio] Configuring extras:tun/tap on ubuntu 12.04

[GNU radio]

Hi

    I have a problem with configuring the gr0 interface for gnuradio on ubuntu 12.04.

The command

$sudo ifconfig gr0 192.168.200.1

does not work and return back error of

SIOCSIFADDR: No such device
gr0: ERROR while getting interface flags: No such device

I have tried a number of methods from the linux community but non of them works.

Does any one in gnuradio community have any clue about it.

Regards