Minimal Raspberry Pi Access Point

Modified: 27/04/2016 22:36

Created: 27/04/2016 22:19

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I needed an access point in my shared flat during my semester abroad in Spain as the shared routers performance dropped significantly when everyone was home. This is how I configured myself a 5 GHz access point using an old Raspberry Pi (Model B) and a Alfa Networks AWUS051NH v2. This networks card supports 5 GHz and N networking. My flat is in the middle of a big block of different apartments and networks, this is a really nice feature to have.

The Raspberry Pi should be up to date with the latest Raspbian or Minibian.

Setup

Install the necessary packages:

apt install raspi-config hostapd bridge-utils wireless-tools iw firmware-linux-nonfree firmware-ralink

Configure hostapd location:

vim /etc/default/hostapd

Configure the DAEMON_CONF:

DAEMON_CONF="/etc/hostapd/hostapd.conf"

Configure hostapd:

vim /etc/hostapd/hostapd.conf

Example:

interface=wlan0
bridge=br0
hw_mode=a
channel=0
ieee80211d=1
country_code=NO
ieee80211n=1
wmm_enabled=1

ssid=blackpi
auth_algs=1
wpa=2
wpa_key_mgmt=WPA-PSK
rsn_pairwise=CCMP
wpa_passphrase=herpaderp

Notable options:

hw_mode: a means 5 GHz (set to g for 2.4)

channel: 0 lets the software choose channel (recommended)

In this setup, the RPi will get its IP address from DHCP, so the only configuration we need to do to the interfaces is to prepare the bridge that wlan0 will use:

vim /etc/network/interfaces

Minimal example:

auto lo eth0 br0
iface lo inet loopback

iface eth0 inet manual

iface br0 inet dhcp
   bridge_ports eth0