One thing I've wanted to build for a long time is a home cluster. Specifically for this I purchased an RPi 4 with 4GB of memory and now it runs the master node of k3s. The first worker node was the RPi 3 you can see on the left. But with just 2GB of RAM it can't do barely anything.
That's when I remembered the two old laptops I had in the attic. So my new project was to disassemble them to minimize power consumption, maybe 3D print a new compact case and connect them to the cluster. That was easier said than done.
Disassembling wasn't that complicated. The adventures started when I tried to run one as a headless node that I could connect to via SSH.
At first I could, and then I couldn't.
Turns out Wifi connection somehow became flaky - it would come up and drop randomly by itself. Mostly it was down. After several attempts to stabilize it, Claude recommended that I connect the new host via cable - apparently you can't rely on Wifi with a headless node.
Okay. Luckily I also had an old Fritz!Box in the attic - I think it was left there by the previous owners of the house, and I was half-sure that I'd thrown it away. But no, I found it! A 14-year-old Fritz!Box 3270.
There I had to disable DHCP (and also learn what DHCP was) so it wouldn't conflict with my main Fritz!Box. And the ex-laptop got connected again!
...Not for long though. After a few minutes it lost connection again. So I had to connect a monitor again and discover that now it couldn't get an IP from either of the Fritz!Boxes, so it self-assigned one. Then I had to force-set another IP matching the local network. And now I think it's done. -_-
That was easier said than done. And I have another laptop I can connect to the cluster!