Watching this pivot-to-ai video I was struck by a thought (as it sometimes happens)… I think “we” may be setting ourselves up for the return of the internet worms, 1999-style, but with a vengeance. Let me explain. Software security in the ’90s In the early days of the public internet, especially as e-mail became widely adopted (mid/late ’90s), a very peculiar thing happened on the client (end user) software side: In the name of progress, some productivity software like the Outlook e-mail client, the Word word-processor and other applications would begin supporting “macros”; little snippets of software written in a high level language such as (at the time) VBScript, embedded inside the data the application would be processing (so embedded inside an e-mail or a document for example).

Here I was going to describe the rough configuration of my four node cluster - however, based on questions I’ve gotten, there was a more pressing issue to address first. First let me just re-iterate why I run the cluster at all: I want a neat little compute cluster at home from which I can serve this web site, my e-mail plus whatever other services I want for hobby purposes at home (like a git repo, file services etc.

A while back, as part of my ever so slightly over-engineered noise reduction effort on the basement cluster, a simple fan manager daemon was developed. Emphasis was on simplicity and small footprint. Now some weeks down the road, looking at systemctl status fanman output, I cannot help but notice that, accumulated, the fan controller software does burn quite some cycles on the CPU. A full 38 minutes and change, from running just around two and a half weeks.

This may lead to accusations of over-engineering, but I solved a problem and had fun while doing so. The four node cluster runs two different types of 5V fan, two fans are fairly quiet but clearly noticeable and two are somewhat loud. All in all the cluster is too loud, and noise aside, it’s silly to be running fans at full tilt when there is no need for cooling. The plan The VisionFive2 board has a 5V fan header, but no electronics behind it to allow regulating (or even switching on/off) the fan.