Setting up an ad hoc network between multiple Rasberry Pis with RTL8188CUS 802.11n WLAN Adapters

Question

I have spent a number of hours trying to set up an ad hoc network between 2 rasberry pis (Debian 7.8 wheezy, kernel version 4.1.6-v7+). I would eventually like to have 11 pis on a single ad-hoc network, but I have not yet managed to establish a connection between 2. Each pi has a USB dongle containing a Realtek RTL8188CUS 802.11n WLAN adapter. Running dmesg | grep usb indicates that the device is being registered with interface driver rtl18192cu. According to this wiki page:

In general, devices with RTL8188CUS work great as wifi access point. If you plan to use your raspberry pi in ad hoc mode, you must verify that your adapter is using the nl80211 driver. Wifi adaptors using RTL8188CUS driver will not work in ad hoc mode.

Does this mean that my device will not be able to use ad hoc mode at all, or that I need to somehow set up my device to use the nl80211 driver?

I have tried following the instructions from this Arch Linux wiki page using both wpa_supplicant and the manual iw method. The iw method does not work, which is consistent with the fact that iw is only for nl80211 compatible devices. Using wpa_supplicant was similarly unsuccessful.

Following the Debian wiki instructions for setting up an ad hoc network yielded better luck through both the manual and /etc/network/interfaces methods in that ifconfig and iwconfig reported that both pis were in ad hoc mode, but they were not able to ping one another. I could also see the ad hoc network from my laptop, but could not connect.

This stackoverflow question has an answer that claims to have had success with the same driver.

Any advice on how to set up an ad-hoc network between multiple rasberry pis would be appreciated. I am particularly interested in receiving help for setting up the wpa_supplicant solution - is there some method of using nl80211 to talk to my wifi device?

Answer 1

Hi this is a bit late on my part but on the same thread I actually posted the answer which I deleted. AdHoc networks with pis are possible with Ralink based WiFi Adapters I use the RT5370 Ralink Driver which makes Adhocing possible with pis

If you need to refer this here is my query which shows that nl80211 drivers aren't much of help

You can trust me with this since I have spent some amount of time trying to develop ad hoc networks for my work and now I can successfully build a network with the Ralink based Adapters without any hassle. Hope it helps

UPDATE -

with Debian Wheezy 7.10 firmware update the EDIMAX adapters are now adhoc compatible now. This has been tested and checked by me personally today. hence there shouldn't be a problem with infrastructure or ad hoc mode of operation for a variety of wifi adapters now

Although tests on Raspbian Jessie seem to fail!