Turn your WLANPi in to test a AP
The WLAN Pi hotspot mode has been created to provide a quick and dirty wireless AP for tasks such as wall attenuation measurements. It will also allow a temporary wireless connection when you'd like to hook up to a switch ethernet port and extend the network connection out to a wireless client. Finally, it can be used to provide wireless access to the WLAN Pi itself if an OTG or Ethernet connection is not available.
If you have WLAN Pi image v1.7 or later, the package is already installed, available and ready to go! Read the notes below to find out how to configure and activate the WLAN Pi hotspot mode.
Background: This package was created using the information in François Vergès blog article : WLAN Pi - Setup a Wi-Fi Hotspot
To use hotspot mode on your WLANPi, you will need:
- a supported wireless adapter plugged in to one USB port of the WLANPi (e.g. CF-912AC, CF-915AC)
- WLANPi distribution v1.7 or later installed on a WLANPi (https://github.com/WLAN-Pi/wlanpi/releases)
It is very likely that you will not want to use this utility with the default shared key, channel and SSID. The defaults are:
- shared key: wifipros
- ssid: wlanpi_hotspot
- channel: 36
To change from default settings, ensure that the WLANPi is operating in standard "classic"mode (i.e. it has not already been switched in to another node such as hotspot or wireless console mode). Then, edit the file: /etc/wlanpihostpot/conf/hostapd.conf. This can be done by opening an SSH session to the WLANPi and using the 'nano' editor:
sudo nano /etc/wlanpihotspot/conf/hostapd.conf
There are numerous fields you can configure to change the behavior of the hotspot access point feature, but here are some of the more likely fields you'll want to look at and perhaps update (note that lines beginning with a # character are comments and do not affect operation):
# WLAN SSID
ssid=wlanpi_hotspot
# WPA-PSK
wpa_passphrase=wifipros
# Mode options: a=5GHz / g=2.4GHz
hw_mode=a
# Set 2.4GHz Channel - 1,6,11
# Set 5GHz Channel - 36,40,44,48,149,153,157,161,165
channel=36
# Set Country Code (Use your own country code here)
country_code=CA
Once you have made your changes, hit Ctrl-X in the nano editor to exit and hit "Y" to save the changes when prompted.
Next, flip the WLANPi in to "Hotspot" mode using the front panel controls of the WLAN Pi. The required front panel option is: "Menu > Modes > HotSpot > Confirm". This will trigger a reboot of the WPAN Pi to switch it into to hotpot mode. After the accompanying reboot, the WLANPi should operate using the parameters configured in hostapd.conf.
If you need to make any subsequent alterations to the parameters configured in hostapd.conf, after making your edits, reboot the WLAN Pi so that they take effect.
Following the WLANPi reboot, your configured hotspot SSID should be available in the network list shown on your wireless client (e.g. laptop).
Once you have joined the SSID, an IP address is assigned to your client device via DHCP and you will have access to the WLAN Pi itself (e.g. SSH to 192.168.88.1). You will be able to access features such as the built-in speedtest utility using a browser pointed at : http://192.168.88.1/
If the Ethernet port of the WLAN Pi is connected to a switch port that can provide an IP address to the WAN Pi, traffic can be forwarded (routed) from your wireless client and out to the Ethernet port. This can be useful to provide an extended network connection from an existing wired network.
(It is possible to flip in to Hotspot mode using the Linux CLI, but it is strongly recommended to use the native WLANPi front panel navigation menu)
As there are quite a few networking changes we need to make for the Hotspot to operate correctly, we need to flip the WLANPi in to a completely new mode of operation that uses a different network configuration. The 'hotspot_switcher' script is used to switch between the usual "classic" mode of operation and the "Hotspot" mode.
When moving to the "Hotspot" mode, various configuration files are changed on the WLANPi, with the original networking files being preserved to allow restoration to the original ("classic" mode) configuration.
When moving back to the original "classic" mode, all changed files are restored to their original state.
When moving between modes, the WLANPi will reboot to ensure that all new network configuration starts cleanly.
To flip the WLANPi in to "Hotspot" mode, SSH to the WLANPi and execute the following command:
sudo /etc/wlanpihotspot/hotspot_switcher on
At this point, the WLANPi will reboot so that the new networking configuration will take effect.
To switch out of "Hotspot" mode, SSH to the WLANPi using network address 192.168.88.1 and run the command:
sudo /etc/wlanpihotspot/hotspot_switcher off
When this command is executed, the original ("classic" mode) networking configuration files will be restored and the WLANPi will reboot. After the reboot, the WLANPi will operate as it did before the switch to "Hotspot" mode.
*** Note: The front panel menu system available from image version v1.7 is a much better option for flipping WLANPi modes as it carried far less risk of causing operational issues ***
Installation (only required by image developers, code is included with WLAN Pi image for regular users)
The install/upgrade process is relatively easy. We simply connect the WLANPi to the Internet and pull the latest files from our GitHub repository. Note that you will lose any customizations you previously applied (e.g. SSID name changes etc.), so back up any config files you need before doing this.
To install (or upgrade) the required files, connect your WLANPi to a network so that it has Internet access. Then SSH to your WLANPi and execute the following commands on the CLI of the WLANPi (make sure you copy & paste each command individually, as you will be prompted to enter a password at some point - use your wlanpi user password):
# Copy & paste these one at a time - you will likely need to enter your password at least once
# You will lose any customizations you previously applied, so back up any config files
# you need before doing this.
cd /etc
sudo rm -r ./wlanpihotspot
sudo git clone https://github.com/WLAN-Pi/wlanpihotspot.git
sudo sh /etc/wlanpihotspot/set_file_permissions.sh
Installation should now be now complete. If you are using the native WLANPi front panel menu system to flip modes and activate the hotspot(which is available from image ver v1.7 & highly recommended!).
