Realtek 8188 Wi Fi adapter
If you are using a Realtek 8188 based wifi adapter, perform the following steps:
Execute
uname -a
Then, read the following post and select the correct driver version:
http://www.raspberrypi.org/forums/viewtopic.php?p=462982#p462982
and select the correct date for kernel driver version
https://dl.dropboxusercontent.com/u/80256631/8188eu-201xyyzz.tar.gz
(x = Year, yy = Month, zz = day)
get the file with the following command:
wget https://dl.dropboxusercontent.com/u/80256631/8188eu-201xyyzz.tar.gz <--set data code for driver version above
tar -zxvf 8188eu-201xyyzz.tar.gz <--set data code for driver version above
sudo install -p -m 644 8188eu.ko /lib/modules/$(uname -r)/kernel/drivers/net/wireless
sudo insmod /lib/modules/$(uname -r)/kernel/drivers/net/wireless/8188eu.ko
sudo depmod -a
In order to use the adapter in AP (Access Point) mode, a custom hostapd executable and configuration is required.
Install the standard 1.0 hostapd following the istructions here
Then, get the customized executable:
wget http://www.daveconroy.com/wp3/wp-content/uploads/2013/07/hostapd.zip
unzip hostapd.zip
sudo mv /usr/sbin/hostapd /usr/sbin/hostapd.old
sudo mv hostapd /usr/sbin/hostapd
sudo chown root.root /usr/sbin/hostapd
sudo chmod 755 /usr/sbin/hostapd
Modify the hostapd configuration with the command:
sudo nano /etc/hostapd/hostapd.conf
Modify the line "driver" as follows:
driver=rtl871xdrv
Save the file and reboot, the configure dnsmasq as explained here