Set up RaspberryPi as Network Router to Powerwall Gateway

RPi-Router.md

RaspberryPi - Powerwall Router

This will set up a Raspberry Pi to connect to a Tesla Powerwall Gateway (TEG) and bridge that connection to the ethernet connected LAN.

Network Configuration

 ___________________          __________________________           _______________
[ Powerwall Gateway ]        [      Raspberry Pi        ]         [      Host     ]
[       TEG         ]  WiFi  [__________________________]   LAN   [ Linux/Mac/Win ]
[   WiFi: TEG-xxx   ] <----  [ 192.168.91.x | 10.0.1.55 ] <-----> [   10.0.1.65   ]
[   192.168.91.1    ]        [  WiFi (dhcp) |  Ethernet ]         [      LAN      ]
 ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾          ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾           ‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
 

Raspberry Pi

1. Create or edit /etc/wpa_supplicant/wpa_supplicant.conf:

network={
        ssid="TEG-xxx"
        psk="password"
}

2. Restart Networking and Test

sudo systemctl restart networking

# Test
ifconfig wlan0
ping -c 1 192.168.91.1

3. Set up IPv4 Routing and Reboot

# Add IP Forwarding - Uncomment net.ipv4.ip_forward=1
sudo sed -i -e '/^#net\.ipv4\.ip_forward=1/s/^#//' /etc/sysctl.conf
sudo sysctl -w net.ipv4.ip_forward=1

# Restart
sudo reboot

Host

On the host, you need to add a route to use the Raspberry Pi as a gateway to get to the Powerwall Gateway.

# Linux
sudo ip r add 192.168.91.0/24 via 10.0.1.55

# MacOS
sudo route add -host 192.168.91.1 10.0.1.55

# Test
ping -c 1 192.168.91.1
curl -ik https://192.168.91.1

It turns out that this isn't really needed. You can set up a connection to the Powerwall TEG IP address direct from the host with a route to 192.168.91.1 via the LAN IP address of the Powerwall (e.g. 10.x.x.x):

# Linux
sudo ip r add 192.168.91.0/24 via 10.x.x.x

# MacOS
sudo route add -host 192.168.91.1 10.x.x.x

# Test
ping -c 1 192.168.91.1
curl -ik https://192.168.91.1