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My 6-node 1U Raspberry Pi rack mount Cluster

Now that I have a half-height rack and a 3D Printer, I figured I should finally move all my Raspberry Pis from sitting in odd places in my office to the rack. And what better way than to print my own 1U Raspberry Pi Rack mount unit?

6 Node Raspberry Pi 1U Rack Mount enclosure - 3D Printed for Pi 4 model B

The rack unit you see above was assembled from 6 'frames', 6 hot-swappable Pi carrier trays, 2 rack mount ears, and a couple lengths of threaded rod for rigidity.

It was printed from these plans from russross on Thingiverse; Russ Ross also made an assembly video, and shows how you can build a 2U 12-Pi enclosure using the same basic design, with interchangeable Pi trays!

Video

There is more detail and a full walkthrough of my home rack in this video:

OBS Task List Overlay for livestream TODO / Checklist

For a few of my task-oriented livestreams, I wanted to be able to have an easy-to-follow list of tasks present in an OBS scene, with an indication of which task was currently in-progress.

I had seen a similar overlay on NASASpaceflight's livestreams (example), and liked the simplicity:

NASASpaceflight Live stream overlay task list for Flight Test

I started searching for an OBS plugin I could use to replicate that overlay, but was coming up with nothing. There was some plugin that seemed like it fit the bill, but it had been abandoned a while back. Most of the other overlays were a lot more specific to gaming, had few options for customization, or only worked with services other than OBS.

Trying KIOXIA CM6 and PM6 Enterprise SSDs on a Raspberry Pi

Late last year, an engineer at Broadcom sent me some hardware and offered some help getting Broadcom's MegaRAID card working on the Raspberry Pi. It took some time, but eventually we were able to get the card and a demonstrator 'UBM' backplane working on the Pi, and it culminated in my posting about Hardware RAID on the Pi, and on a livestream, getting 16 hard drives working on a Pi.

The one thing I couldn't test in those earlier videos was the backplane and storage card's 'Tri-mode' support, allowing PCI Express NVMe drives—like KIOXIA's CM6—to work in the same slot as the SATA and SAS drives I was used to testing.

So after some conversation with reps at KIOXIA, I was able to get a PM6 and three CM6 drives on loan to test them:

KIOXIA CM6 and PM6 SSD with Raspberry Pi Compute Module 4

Tried Nvidia's GTX 1080 - still no external GPU on a Pi

Earlier today I did a livestream on my YouTube channel to attempt using an Nvidia GeForce GTX 1080 on a Raspberry Pi Compute Module 4.

MSI Nvidia GeForce GTX 1080 Graphics Card GPU

As with all my testing, I'm documenting everything I learn in this GitHub issue, which is part of the Raspberry Pi PCI Express Card Database website.

It's only been a few hours, but I've already gotten good suggestions for better debugging than I was able to do on the stream. And someone pointed out it might be the case, due to 32-bit memory limitations on the BCM2711's PCIe bus, that no GPU with more than 4 GB of onboard RAM could work. Though it's hard to confirm there'd be no software workaround—even 1 and 2 GB graphics cards (AMD and Nvidia) are crashing the kernel in similar ways.

The full livestream is available on replay and is embedded below:

Taking control of the Pi PoE HAT's overly-aggressive fan

I am starting to rack up more Pis (quite literally) using the official Pi PoE HAT to save on cabling.

The one thing I hate most about those little HATs is the fact the fans spin up around 40°C, and then turn off a few seconds later, once the temperature is back down to 39 or so, all day long.

I'd be happy to let my Pis idle around 50-60°C, and only have the little whiny fans come on beyond those temperatures. Even under moderate load, the Pi rarely goes above 55°C in my basement, where there's adequate natural convection, so the fans would only really be necessary under heavy load.

Beautiful 3D Print time-lapses with my Nikon D700 and Octolapse

After seeing GreatScott's video on creating great 3D Printing timelapses, I knew I had to make better 3D Print timelapses using one of my DSLRs.

I had already tried using my pi-timelapse script with a Pi Zero W and the Camera Module v1 and v2, but the quality is just so-so, plus it's not synchronized with the 3D printer, therefore at least on the Ender 3 V2, the printed object goes all over the place:

Unstabilized Pi Timelapse of 3D Print on Ender 3 V2 without OctoPrint or Octolapse

What I wanted was a stable and sharp timelapse of the entire process with high enough resolution to use in HD videos I produce for my YouTube channel.

So how did I get it working with my old but trusty Nikon D700? Read on...