Thanks!

What are the use cases for taking it with you instead of just connecting to your homelab?

I built it just to see how much I could cram onto a Pi Zero clone/how many self-hosted services I could have on something I can fit on my keychain, and the answer was "a lot". It's something of a travel server, travel router, emergency backup server, etc.

I mainly just wanted a subset of my homelab services available in something I could take with me anywhere. Home lab could go down while away, power could go out, something to use while glamping, can take it with me if there's ever an emergency where I have to evacuate, etc.

What started out as a single unit has become a three unit portable stack lol. Yay feature creep!

Services

• Jellyfin (all content pre-transcoded so everything can direct stream)
• CodeServer (setup for Python, NodeJS/Bun + React, and Platform.IO for ESP8266/ESP32 development)
• Kiwix (including the full Wikipedia dump with images as well as offline docs for lots of code libraries I work with, etc)
• SearxNG so I always have a sane search engine available
• CalibreWeb with my whole ebook library
• MPD+Snapcast+My whole music library. Also has myMPD web UI for controlling MPD. Snapcast clients can connect, and it can serve multi-speaker/multi-room audio
• PiHole serving both ad blocking and local DNS as well as providing DHCP for the access point
• PairDrop for sending/receiving files
• NodeRED and Mosquitto MQTT for setting up ad-hoc automations
• Nginx with real LetsEncrypt certs so all services have valid SSL certs and hostnames

Networking

• One USB port is configured in ethernet gadget mode. Can plug it into a host PC and get an IP address from it
• One wifi adapter is setup as an AP and is bridged with the USB ethernet (a PC plugged in and a wifi client are on the same L2 plane).
• The second wifi is the "WAN" connection if one is available. Can alternatively connect to USB tethering on my phone
• If there is any kind of "WAN" upstream, the LAN bridge (USB ethernet/Wifi) will route to it
• Wireguard to connect back to my homelab.

File Services

• Samba
• Encrypted LUKS volume for critical docs (tax records, vet records for the dogs, etc)

I've got a second unit that connects as a client to the main one with some additional backup services:

• Email stack( Dovecot, Postfix, SpamAssassin, ClamAV, Webmail)
• Matrix/Synapse stack
• Asterisk
• Snapcast client

The second one is basically a backup to my main stack in case of disaster/power outage/etc. Those all tunnel to a cloud VPS + load balancer and only need an internet connection to setup the tunnels to receive traffic from the VPS (and route back out to it). Those services are stopped and a cron task keeps them in sync with the main ones in my homelab. If I need to fail over, I just SSH into the VPS and re-route traffic to them instead of my homelab endpoints.

I self-host my own email and chat and phone services, so those have become critical services I want to always have online. Essentially these little Pi clones are a backup stack for my most used services and one that is both extremely low power and portable should I ever need to host them on the go (house burns down, have to evacuate due to emergency, etc).

Third Unit (Still on the bench)

I have a third unit that's built on a PiZero2W but it's still on the workbench (but functional!). Just haven't gotten any kind of case at all built for it.

It's got two RTL-SDR units attached. One is tuned to the NOAA weather radio station and feeds into Snapserver on the main unit (so you can listen to the weather radio anywhere on the network) as well as piped into Meshtastic EAS-SANE alerter in order to forward emergency alerts to Meshtastic. There's a USB-connected Meshtastic node attached as well for that.

The second RTL-SDR is setup as a generic FM radio tuned to the local variety station. It's just piped to Snapserver on the main unit to make it available on the network.

I may convert the second SDR into a ADS-B listener, but for now, I like having the FM radio available.