I just found this thread; apparently I'm not the first to run into this.

It really seems like the docs should be updated to note that they won't actually work unless (apparently) you have set up external USB storage.

I don't understand how I could set up USB storage — my Omega2 board does not even have a USB port (apart from the micro-USB on the breadboard dock which I'm using to power it). And moreover, if the Omega needs an external board providing a USB interface, plus a USB drive, just to run Python light and (in my case) the MQTT module, then it's no longer the tiny, simple solution I thought it was — I may as well run an Raspberry Pi, which at least has an SD slot built in.

Feeling discouraged, but hoping there's some good solution I have missed.

I just received my Omega2, and am trying to follow these instructions to get set up with Python3 (intending to then install paho-mqtt and get my device sending some MQTT messages from simple Python scripts). But I've run into a problem: it seems I'm already out of space.

root@Omega-596D:~# opkg install python3-pip
Installing python3-pip (8.1.2-1) to root...
Collected errors:
 * verify_pkg_installable: Only have 288kb available on filesystem /overlay, pkg python3-pip needs 886
 * opkg_install_cmd: Cannot install package python3-pip.

Since turning this thing on, I have literally installed only:

1. nano
2. python3-light

...and then step 3 was going to be installing pip (so I could do step 4, install paho-mqtt). Oh, and I've added one 24-byte text file (greeting.py) for testing Python.

The docs sure seem to imply that I should be able to install python3-light and pip. For that matter, they make it sound like you could install the full version of python and still use pip if you really wanted to. And it's hard to imagine that nano is so big it's filled my storage space. Have I screwed up somehow? How do I view and manage my file space?

I've just gotten my Omega 2 board today, and I'm thinking along very similar lines — I want my Onion boards to either send MQTT messages when something happens to their connected hardware, or do something with that hardware according to MQTT messages received.

Like you (Sebastian), I see no point in running an MQTT broker on the device — the broker will be elsewhere; these are edge devices that should merely be MQTT clients.

I see you solved it by using some clever files and shell scripting. But did you consider using Python? From other threads, it looks like paho-mqtt can be installed for python, which should make it pretty easy (and possibly more efficient) to subscribe to topics and do stuff in response (or conversely, to publish MQTT messages in reaction to anything you can sense in Python).

Just wondering if I am somehow barking up the wrong tree, or whether this is a sensible way to do it.