Build an offline library hub with a Raspberry Pi and solar power

A Raspberry Pi with an SSD, running Kiwix and a Wi-Fi hotspot, serves the whole archive to any phone or laptop with no internet. Use the setup script, copy ZIM files to /srv/library, and keep a second drive.

Part of Day Zero, the plan for an AI-related crisis that gets out of control. Why it exists. General information, not medical advice: how these guides are reviewed.

A hub is a small computer with the archive on a drive. It makes its own Wi-Fi network, and anyone nearby can open it on a phone, tablet or laptop with no internet and no app. One hub serves a whole camp.

Parts

• A Raspberry Pi 4 or 5 (or any small Linux computer with Wi-Fi), a power supply and a case.
• A storage drive: a 256 GB to 2 TB SSD in a USB enclosure, or a large SD card (a USB SSD is more reliable).
• Power: 12 V battery with a 5 V converter, a 50 to 100 W solar panel and a charge controller. A Pi draws about 3 to 10 W. See reader power.
• A spare of everything that can fail: card, cables, charger.

Setup

On a computer with internet (today), prepare the hub:

1. Install Raspberry Pi OS Lite on the card using Raspberry Pi Imager. Set a username, password and enable SSH.
2. Start the Pi, connect it to the internet by cable, and copy the setup script to it:

curl -fsSLO https://www.toswo.com/offline-hub/setup.sh
less setup.sh
sudo bash setup.sh

Read the script before you run it. It installs Kiwix, makes the Wi-Fi hotspot TOSWO-Library, and starts the library at boot.

1. Copy your .zim files from the Downloads page into /srv/library/, then run sudo systemctl restart toswo-library.
2. Check: connect a phone to TOSWO-Library and open http://10.42.0.1.

Print the instructions

Print this page and tape it to the case. In a crisis nobody will be able to look it up.

Keep it working

• Keep a second drive, copied from the first, in a different place.
• Update the files once a month while the internet works. See Downloads.
• Test restarting it from cold. Test it on battery.
• Protect from damp, dust and heat. Keep silica gel in the case.

Limits

The script has been written for Raspberry Pi OS but Toswo has not tested it on every board. Try it before you need it, and fix what breaks.

Review status: not yet checked by a named professional. Read how these guides are reviewed and check anything medical or dangerous with a qualified person where you can.