Nothing Was Using the Cores: Three Idle Arm64 Boards, One HA k3s Cluster, and a BSD Build Farm
I had three small Arm64 boards on a shelf, each doing one modest thing and idling the rest of the time — an Orange Pi 5 Max running an occasional local LLM, two Raspberry Pi–class machines mostly serving a web page. Between them they had sixteen cores, forty gigabytes of RAM, and four terabytes of NVMe, and almost none of it was doing anything at any given moment. This is the story of resisting the urge to buy two more boards into a memory shortage, and instead turning that idle majority into a real three-node HA k3s cluster with embedded etcd, then teaching it to do the job the boxes had quietly been built for all along — compiling native FreeBSD, OpenBSD, and NetBSD Arm64 binaries — and the small pile of gotchas that stood between "three SBCs" and "a build farm," from a big.LITTLE crash loop to golden images that turned out to be live disks. And then everything else the reclaimed capacity paid for.
