Smart House

I've finally got round to installing Home Assistant on my file server. This is the first time I've played with virtual machines since transplanting the hard drives from an Intel box to an AMD box, and I needed to purge and reinstall bits of KVM / QEMU to get it to work.

Of course now it's up and running it doesn't do very much on its own. There are various things it can theoretically do which I'm interested in, including tracking Gary around the house using a tag on his harness. But my starting point is pretty simple - measuring temperature and humidity in every room in the house.

The design principle is pretty solid - I plug a USB Zigbee stick into my fileserver, and it should be able to reach devices across the house. I buy some Zigbee sensor units from AliExpress for about a fiver a pop, pair them with the contoller, and deploy them around the house. Home Assistant handles monitoring, logging, graphing and alerting. Maybe I need a Zigbee router/repeater unit on the landing because my house is basically a Faraday cage, but that should be the only complication.

In practice, I've pretty much immediately hit a brick wall with this. Either I choose between ready-to-use units (which tend to use WiFi and are much more expensive per-unit), or I go for something slightly more homebrew and run into a host of problems. I've seen advice that you shouldn't use Bluetooth (as Linux support isn't good enough) or Zigbee (as Linux support is too good for the devices out there), the two cheap low-power alternatives. Or I go the ESPHome approach and solder things together myself, which is pretty much a non-starter at my skill level.

I suspect I'll end up just buying some random units from AliExpress and seeing what works, but it's frustrating that I either have to do this kind of expensive, slow trial-and-error or pay through the nose for what should be cheap kit.

Random Encounter

This afternoon I was over by Manchester University after an appointment. The streets are bustling with Fresher's Week students, and I was sat on a bench in the sunshine enjoying a mushroom burrito.

A lady asks if she can sit next to me in an accent not unlike cosmolinguist so I ask her where she's from. She's Canadian, from Toronto, and she's waiting for her daughter who's just started Uni. We get to talking about all sorts of things while she waits, about life in Manchester, about crime (she's a prosecutor, and so is her husband).

We talk about the recent race riots in the city centre and how I ended up escorting queers and foreigners to their respective destinations when our bus was cancelled. How there were more of us at Trans Pride than there were fascists. About how you can spot the good "foreign" restaurants by the ethnicity of the diners, and how big city life differs from growing up in the countryside.

It was a delightful way to spend time, and when her daughter arrived I got to wish her well in her studies before heading home.