airmon-ng

• this script can be used to enable monitor mode on wireless interfaces. It may also be used to go back from monitor mode to managed mode

Usage Examples

Check the status and/or listing of Wireless Interfaces

~# airmon-ng
PHY	Interface	Driver		Chipset

phy0	wlan0		ath9k_htc	Atheros Communications, Inc. AR9271 802.11n

Checking for Interfering Processes

When putting a card into monitor mode, it will automatically check for interfering processes. It can also be done manually by running the following command:

~# airmon-ng check
Found 5 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
  718 NetworkManager
  870 dhclient
 1104 avahi-daemon
 1105 avahi-daemon
 1115 wpa_supplicant

Killing Interfering Processes

This command stops network managers and then kills interfering processes left:

~# airmon-ng check kill
Killing these processes:

  PID Name
  870 dhclient
 1115 wpa_supplicant

Enable Monitor Mode

Info

It is very important to kill the network managers before putting a card in monitor mode!

~# airmon-ng start wlan0
Found 5 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
  718 NetworkManager
  870 dhclient
 1104 avahi-daemon
 1105 avahi-daemon
 1115 wpa_supplicant

PHY	Interface	Driver		Chipset

phy0	wlan0		ath9k_htc	Atheros Communications, Inc. AR9271 802.11n
		(mac80211 monitor mode vif enabled for [phy0]wlan0 on [phy0]wlan0mon)
		(mac80211 station mode vif disabled for [phy0]wlan0)

As you can see, it created a monitor mode interface called wlan0mon and it notified there are a few processes that will interfere with the tools.

Disable Monitor Mode

~# airmon-ng stop wlan0mon
PHY	Interface	Driver		Chipset

phy0	wlan0mon	ath9k_htc	Atheros Communications, Inc. AR9271 802.11n
		(mac80211 station mode vif enabled on [phy0]wlan0)
		(mac80211 monitor mode vif disabled for [phy0]wlan0mon)

Don’t forget to restart the network manager. It is usually done with the following command:

sudo service NetworkManager restart

Resources

• https://www.aircrack-ng.org/doku.php?id=airmon-ng