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Wireshark-users: Re: [Wireshark-users] monitor mode

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Fri, 8 Mar 2013 10:57:55 -0800
On Mar 8, 2013, at 10:22 AM, bart sikkes <b.sikkes@xxxxxxxxx> wrote:

> it might be the case you don't have your interface in monitor mode.
> you could try to set it as such: iwconfig wlan0 mode monitor

If you do that, it might fail; I tried it on Ubuntu 12.04 with a Zydas-based Belkin USB stick and it got

	Error for wireless request "Set Mode" (8B06) :
	    SET failed on device wlan0 ; Device or resource busy.

I don't know if that's NetworkManager getting in the way or not.

> or use another tool like airmon-ng [1] to do create a virtual interface in
> monitoring mode.

airmon-ng is my recommendation in these cases.  It has a large bag of tricks for dealing with the twisty little maze of Wi-Fi drivers on Linux, many different (although I think mac80211 drivers would all be treated the same; airmon-ng handles that).