Hamptons Backyard Pi Zero – Handover Setup and Recovery Guide

1. Set Up the Pi as a Wi-Fi Hotspot (Handover)

Use when: Setting up a self-contained control system so irrigation, lighting, and automation continue to operate without relying on external Wi-Fi or internet. This is also used when preparing the system for handover, allowing a new occupant to immediately connect via tablet or laptop and operate or modify the setup without any network configuration.

Install Required Packages

sudo apt update
sudo apt install hostapd dnsmasq -y

sudo systemctl stop hostapd
sudo systemctl stop dnsmasq

Backup Existing Configuration

sudo cp /etc/dhcpcd.conf /etc/dhcpcd.conf.backup

if [ -f /etc/dnsmasq.conf ]; then
    sudo cp /etc/dnsmasq.conf /etc/dnsmasq.conf.backup
fi

Configure Static IP

Edit:

sudo nano /etc/dhcpcd.conf

Add to the end of the file:

interface wlan0
static ip_address=192.168.4.1/24
nohook wpa_supplicant

Configure DHCP Server

Backup the default file:

sudo mv /etc/dnsmasq.conf /etc/dnsmasq.conf.orig

Create a new configuration:

sudo nano /etc/dnsmasq.conf

Contents:

interface=wlan0
dhcp-range=192.168.4.2,192.168.4.50,255.255.255.0,24h

Configure Wi-Fi Access Point

Create:

sudo nano /etc/hostapd/hostapd.conf

Contents:

interface=wlan0
driver=nl80211
ssid=BackyardPi
hw_mode=g
channel=6
wmm_enabled=0
auth_algs=1
wpa=2
wpa_passphrase=[REPLACE_WITH_PASSWORD]
wpa_key_mgmt=WPA-PSK
rsn_pairwise=CCMP

Point hostapd to the Configuration

Edit:

sudo nano /etc/default/hostapd

Set:

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

Enable Services

sudo systemctl unmask hostapd
sudo systemctl enable hostapd
sudo systemctl enable dnsmasq

Reboot

sudo reboot

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2. Confirm the Hotspot Is Working (Direct Connect)

Use when: After setup or changes, to verify devices can connect reliably, Backyard Pi is accessible, IP assignment is correct, and the system recovers properly after reboot or power loss.

Connect a Device

Connect a laptop, phone or tablet to:

SSID: BackyardPi
Password: <your password>

Verify IP Address Assignment

The connected device should receive an address in the range:

192.168.4.2 - 192.168.4.50

Verify Node-RED

Open:

http://192.168.4.1:1880

If using the Node-REd Dashboard:

http://192.168.4.1:1880/ui

Verify SSH Access

ssh pi@192.168.4.1

Verify Automatic Recovery

1. Power off the Pi.
2. Wait 10 seconds.
3. Power it back on.

Confirm:

• Hotspot appears automatically.
• Devices reconnect automatically.
• Node-RED is accessible.

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3. Revert Hotspot and Connect to a New Wi-Fi Network (Recovery)

Use when: Moving the system from standalone operation to integration with an existing Wi-Fi network, typically when a new owner wants broader network access, remote control, or integration with their own infrastructure.

Connect to the Pi Hotspot

Connect your laptop to:

SSID: BackyardPi

SSH into the Pi:

ssh pi@192.168.4.1

Restore Normal Wi-Fi Configuration

Edit:

sudo nano /etc/dhcpcd.conf

Remove:

interface wlan0
static ip_address=192.168.4.1/24
nohook wpa_supplicant

Alternatively restore the backup:

sudo cp /etc/dhcpcd.conf.backup /etc/dhcpcd.conf

Restore dnsmasq Configuration

sudo rm -f /etc/dnsmasq.conf

if [ -f /etc/dnsmasq.conf.orig ]; then
    sudo mv /etc/dnsmasq.conf.orig /etc/dnsmasq.conf
fi

Configure the New Wi-Fi Network

Run:

sudo raspi-config

Navigate to:

System Options
  → Wireless LAN

Enter:

• New SSID
• New Password

Disable Hotspot for Future Boots

Do not stop the services, as this will disconnect your current session.

Instead disable them so they do not start after the reboot:

sudo systemctl disable hostapd
sudo systemctl disable dnsmasq

Reboot

sudo reboot

The hotspot will remain active until the Pi reboots.

After reboot:

• The hotspot will no longer be available.
• The Pi will connect to the configured Wi-Fi network.
• Connect your laptop to the same Wi-Fi network.
• Access the Pi using its new IP address.

Find the Pi's New IP Address

Check your router's DHCP client list and locate the Raspberry Pi.

Connect using:

ssh pi@<pi-ip-address>

Or access Node-RED:

http://<pi-ip-address>:1880

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4. Change to a New Wi-Fi Network

Use when: Updating Wi-Fi credentials after router changes or network updates while keeping all system services running without interruption.

Run raspi-config

sudo raspi-config

Navigate to:

System Options
  → Wireless LAN

Enter:

• New SSID
• New Password

Reboot

sudo reboot

Confirm Connection

Check the router's DHCP client list and locate the Raspberry Pi.

Confirm Node-RED is available:

http://<pi-ip-address>:1880