WLAN Pi Server Mode

WLAN Pi Server mode for the RPi/CM4 based platforms

(Note: In this initial version, only 2.4GHz operation is supported due to platform support issues - this is under investigation)

Turn your WLAN Pi into a DHCP server, TFTP server and terminal server (Wi-Fi Console) at the same time

The WLAN Pi server mode enables use cases like lab build, software upgrade of your network appliances or AP and staging with no additional servers or apps. Simply plug your WLAN Pi into your lab switch and let it provide all services.

If you plug a Wi-Fi adapter to its USB port, the WLAN Pi will broadcast wlanpi_server SSID which makes it easier for you to wirelessly access the wired network.

A Word of Caution

Server mode enables DHCP server on the wired eth0 interface of the WLAN Pi. Only plug this interface to a network which is under your management. Never connect WLAN Pi in Server mode to a production network. It can distrupt production services !!!

Subnets

• Wired subnet: 172.16.42.0/24
• Wireless subnet: 172.16.43.0/24

Requirements

To use server mode on your WLAN Pi, you will need:

• WLAN Pi Pro device

Configurations Options

It is very likely that you will not want to use this utility with the default shared key, channel and SSID. The defaults are:

• ssid: wlanpi_server
• shared key: wifipros
• channel: 6

To change from default settings, ensure that the WLAN Pi is operating in its default "classic" mode. Then edit the file: /etc/wlanpi-server/conf/hostapd.conf. This can be done by opening an SSH session to the WLANPi and using the 'nano' editor:

 ssh [email protected]
 sudo nano /etc/wlanpi-server/conf/hostapd.conf

There are numerous fields you can configure to change the behaviour of the server mode 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_server

    # 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=GB

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 WLAN Pi in to "Server" mode using the front panel buttons by navigating to "Menu > Modes > Server > Confirm". This will trigger a reboot of the WLAN Pi to switch it into the Server mode.

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.

Server Mode is Non-persistent

WLAN Pi will only stay in server mode until you reboot it or remove power source. At the next boot, it will automatically switch back to its default "Classic" mode. If you need to activate it again, do so by "Menu > Modes > Server > Confirm". This is a safety feature to help you avoid WLAN Pi in server mode (with DHCP server enabled) to be connected to a production network by mistake.

Using Server Mode

Following the WLAN Pi reboot, your configured server mode SSID should be available in the network list shown on your wireless client.

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 172.16.43.1). You will be able to access features such as the built-in speedtest utility using a browser pointed at: http://172.16.43.1/

Plug the Ethernet port of the WLAN Pi to your lab switch and it will provide IP addresses to the wired devices.