Issue: When doing
iwconfig wlan0 mode master I get the following error:
root@OpenWrt:~# iwconfig wlan0 mode master Error for wireless request "Set Mode" (8B06) : SET failed on device wlan0 ; Invalid argument.
Root cause + solution:
Due to this, the old method of issuing
iwconfig <wireless interface> mode master no longer works. Userspace programs like hostapd now use netlink (the nl80211 driver) to create a master mode interface for your traffic and a monitor mode interface for receiving and transmitting management frames.