#Wifi hotspot with Edimax 7811Un and Raspberry Pi 2 (Raspbian Wheezy)

adapted from: http://prograssing.com/news/how-to-setup-a-wlan-hotspot-with-rasperry-pi-2-edimax-7811un-and-huawei-e3372/
and: https://frillip.com/using-your-raspberry-pi-3-as-a-wifi-access-point-with-hostapd/

##Step 1: Hostapd for Edimax EW 7811Un
sudo apt-get install hostapd dnsmasq
wget http://www.juergenkeil.de/download/hostapd-2.2.rtl871xdrv.gz
gunzip hostapd-2.2.rtl871xdrv.gz
sudo mv /usr/sbin/hostapd /usr/sbin/hostapd.orig
sudo mv hostapd-2.2.rtl871xdrv /usr/sbin/hostapd-2.2.rtl871xdrv
sudo chmod +x !$
sudo ln -s !$ /usr/sbin/hostapd

##Step 2: Hostapd configuration

# 2.1
sudo nano /etc/default/hostapd
Change this:
#DAEMON_CONF=""

With this:
DAEMON_CONF="/etc/hostapd/hostapd.conf"

ctrl-X + O #save modification

# 2.2 configuration file
sudo nano /etc/hostapd/hostapd.conf

-------------------
/!\ Important parts:
    driver=rtl871xdrv
    noscan=1
-------------------

Content:

    # the name of the WiFi interface we configure
    interface=wlan0
    
    # we use the specific driver for the Edimax 7811Un
    driver=rtl871xdrv

    # the name of the hotspot
    ssid=Raspoid

    country_code=BE

    # use channel 6
    channel=6

    # QoS support
    wmm_enabled=1

    # WPA2 only
    wpa=2

    # 1=wpa, 2=wep, 3=both
    auth_algs=1

    # the network passphrase
    wpa_passphrase=jaWPZ57t8nvR

    # use a pre-shared key
    wpa_key_mgmt=WPA-PSK

    #wpa_pairwise=TKIP
    wpa_pairwise=CCMP

    # use AES, instead of TKIP
    rsn_pairwise=CCMP

    # accept all MAC addresses
    macaddr_acl=0

    eap_server=0
    eapol_key_index_workaround=0
    own_ip_addr=127.0.0.1

    # use the 2.4GHz band
    hw_mode=g

    ieee80211d=1

    # 802.11n support
    ieee80211n=1
    ht_capab=[SHORT-GI-20][SHORT-GI-40][HT40+][DSSS_CCK-40][MAX-AMSDU-7935]
    #noscan=1
    eap_reauth_period=0
    max_num_sta=8
    beacon_int=100

# 2.3 configure wlan0 interface

sudo nano /etc/network/interfaces

##Step 3: Dnsmasq Configuration

#Backup of default conf.
sudo mv /etc/dnsmasq.conf /etc/dnsmasq.conf.orig  
sudo nano /etc/dnsmasq.conf


Content:

interface=wlan0      # Use interface wlan0  
bind-interfaces      # Bind to the interface to make sure we aren't sending things elsewhere  
server=8.8.8.8       # Forward DNS requests to Google DNS  
domain-needed        # Don't forward short names  
bogus-priv           # Never forward addresses in the non-routed address spaces.  
dhcp-range=192.168.0.50,192.168.0.150,12h # Assign IP addresses between 192.168.0.50 and 192.168.0.150 with a 12 hour lease time  

# Step 4: enable ipv4 forwarding
sudo nano /etc/sysctl.conf
Simply uncomment the following line:
#net.ipv4.ip_forward=1

# Step 5: Share internet connection from eth0
We need to configure a NAT between our wlan0 interface and our eth0 interface.
We can do this using the following commands:

sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE  
sudo iptables -A FORWARD -i eth0 -o wlan0 -m state --state RELATED,ESTABLISHED -j ACCEPT  
sudo iptables -A FORWARD -i wlan0 -o eth0 -j ACCEPT