How to fix "ioctl(SIOCGIFINDEX) failed: No such device"?

root@Sphinx-PC:~#
root@Sphinx-PC:~# 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 run 'airmon-ng check kill' PID Name 899 avahi-daemon 920 NetworkManager 922 wpa_supplicant 966 avahi-daemon 1096 dhclient
PHY Interface Driver Chipset
phy0 wlp7s0 ath9k Qualcomm Atheros AR9485 Wireless Network Adapter (rev 01)
root@Sphinx-PC:~#
root@Sphinx-PC:~#
root@Sphinx-PC:~# airodump-ng mon0
Interface mon0:
ioctl(SIOCGIFINDEX) failed: No such device
root@Sphinx-PC:~# 

4 Answers

when you try

root@Sphinx-PC:~# airodump-ng mon0
Interface mon0: 

you can't find interface mon0, instead interface wlp2s0
your wlan0 has become wlp2s0 as mon0

Try

airmon-ng start wlan0
airodump-ng wlp2s0

Try running this:

sudo airmon-ng

It shows the following on my device:

PHY Interface Driver Chipset
phy0 wlp1s0 ath9k Qualcomm Atheros QCA9565 / AR9565 Wireless Network Adapter (rev 01)

Here you can see that my device's interface is wlp1s0 and you can start it like this:

sudo airmon-ng start wlp1s0

The interface name may be different for you. You might get something like this:

Found 4 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 run 'airmon-ng check kill' PID Name 689 avahi-daemon 696 avahi-daemon 705 NetworkManager 818 wpa_supplicant
PHY Interface Driver Chipset
phy0 wlp1s0 ath9k Qualcomm Atheros QCA9565 / AR9565 Wireless Network Adapter (rev 01) (mac80211 monitor mode vif enabled for [phy0]wlp1s0 on [phy0] wlp1s0mon) (mac80211 station mode vif disabled for [phy0]wlp1s0)

You can see [phy0]wlp1s0 on [phy0] wlp1s0mon: this is the name of my device's interface, so in this case I run this:

airodump-ng wlp1s0mon

and it works for me.

I had the same problem, I tried this and it works.

first I typed:

PC@PC:~#$ sudo airmon-ng
Interface Chipset Driver

then

PC@PC:~#$ airmon-ng start <Interface>
Interface Chipset Driver
<Interface> <Chipset> <Driver> (monitor mode enabled on <mon0>)

Now, Interface is ready to use, finally I typed:

PC@PC:~#$ airodump-ng mon0
BSSID PWR Beacons #Data, #/s CH MB ENC CIPHER AUTH ESSID

First try this

/usr/bin/airmon-ng

Using this you see interfaces, such as wlan0mon.

Then try this

airmon-ng start wlan0mon

and after that

airodump-ng wlan0mon