root@bt:~# airmon-ng start wlan0


Found 2 processes that could cause trouble.
If airodump-ng, aireplay-ng or airtun-ng stops working after
a short period of time, you may want to kill (some of) them!

PID	Name
1336	dhclient3
1732	dhclient3
Process with PID 1732 (dhclient3) is running on interface wlan0


Interface	Chipset		Driver

wlan0		Ralink RT2870/3070	rt2800usb - [phy0]
				(monitor mode enabled on mon4)
mon0		Ralink RT2870/3070	rt2800usb - [phy0]
mon1		Ralink RT2870/3070	rt2800usb - [phy0]
mon2		Ralink RT2870/3070	rt2800usb - [phy0]
mon3		Ralink RT2870/3070	rt2800usb - [phy0]