3

I am trying to make RaLink RT 5370 WiFi adapter run in dual mode - station as well as AP. I have tiny core linux installed on PI, built on top of 3.18.10 linux kernel version. I have been able to make dual mode work effectively on Atheros based adapter, but the same steps do not work for RT5370. Once PI connects to WiFi through wlan0 interface, I fire the below sequence of commands -

#1. To create wlan1 in Master mode
iw dev wlan0 interface add wlan1 type __ap

#2. To assign IP to wlan1 interface
ifconfig wlan1 up 192.168.7.1

The above command fails with the error -

ifconfig: SIOCSIFFLAGS: Device or resource busy

and I cannot proceed further. The later steps include bringing up dnsmasq and hostapd.

So, is this driver limitation? And is there a workaround?

-1

It looks like your H/W is not providing you a dual-mode. Actually, as my personal experience shows, ONLY 2 or 3 antennas on adapter can give you a POSSIBILITY of running in dual-mode. I saw an USB-dongle, that ACTUALLY supported it, but due to single antenna construction it's perfomance was awful in dual-mode, but very good as just AP or ST.

  • But the Atheros wifi adapter for which dual mode worked, has a single antenna. Also, when first command is fired, iwconfig does show 2 interfaces wlan0 on STA mdoe and wlan1 on Master mode. The problem arises when I fire second command. Also, if I set wlan1 on Monitor mode instead of Master mode, even the second command works, but later hostapd fails with the same error message. – deveshchanchlani Jan 26 '16 at 2:48
  • The number of antennas should not matter. It won't be transmitting to multiple destinations at the same time anyway as usually, if it can be both a STA and AP at the same time, the AP portion will be locked to the same frequency the STA side uses. – Michael Graff Jan 26 '16 at 6:44
  • @MichaelGraff it should not - I agree, but IT DOES. If I wouldn't checked it myself I was never write such a thing. It took me a while to figure it out, and it worked – Alexey Vesnin Jan 26 '16 at 14:32
  • 1
    Dual antennas does not imply dual radios. This feels antidotal not scientific. – Michael Graff Jan 27 '16 at 5:22
  • 1
    I never said two radios should share a single antenna. I said two antennas does not imply two radios. – Michael Graff Jan 27 '16 at 14:08

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.