In my video about the brand new Raspberry Pi 5, I mentioned the new external PCIe port makes it possible to boot the standard Pi 5 model B directly off NVMe storage—an option which is much faster and more reliable than standard microSD storage (even with industrial-rated cards!).
Enabling NVMe boot is pretty easy, you add a line to /boot/firmware/config.txt, modify the BOOT_ORDER in the bootloader configuration, and reboot!
I recently got an Nvidia Jetson Nano 2GB Developer Kit, and I read through and followed the Developer Kit Getting Started Guide straight from Nvidia's website.
I downloaded the 7 GB(!) microSD card from their website, and flashed it to a 128 GB microSD card using Balena Etcher.
Then I popped the microSD card into my dev kit board, plugged in HDMI and a USB-C 3A power supply, and waited... I kept seeing a giant NVIDIA logo on my display, and after about 20 seconds, it would seemingly reboot to black screen, then the logo... and repeat forever.
Searching around the Nvidia forums, I eventually found this issue: Nano 2GB boot looping, and finally found the problem: apparently the default image download is only for the 4GB Nano model.
This blog post starts with the question: If I cut the ports off a Raspberry Pi 4 model B, will it still work?
My early conclusion? Sorta.
With most Raspberry Pi generations, there is a full-featured model B, and a smaller, trimmed-down model A. The Pi 4 never had a model A, so I thought it would be interesting to see if I could make one. I looked at the Pi 4 with this really cool X-ray tool, as well as using this album of X-ray images from reddit user u/xCP23x:
The cut was calculated to try to avoid anything important, though as we'll find later it may not have been measured carefully enough.
When the Compute Module 4 was released (see my CM4 review here), I asked the Pi Foundation engineers when we might be able to boot off NVMe storage, since it was trivially easy to use with the exposed PCIe x1 lane on the CM4 IO Board.
The initial response in October 2020 was "we'll see". Luckily, after more people started asking about it, beta support was added for direct NVMe boot just a couple weeks ago.
Out of the box, to conserve power, the new Raspberry Pi Compute Module 4 doesn't enable its built-in USB 2.0 ports.
You might notice that if you plug something into one of the USB 2 ports on the IO Board and don't see it using lsusb -t. In fact, you see nothing, by default, if you run lsusb -t.
To enable the USB 2.0 ports on the Compute Module 4, you need to edit the boot config file (/boot/config.txt) and add:
dtoverlay=dwc2,dr_mode=host
Then reboot the Pi. Now you should be able to use the built-in USB 2.0 ports!
For many of my Ansible playbooks and roles, I have CI tests which run over various distributions, including CentOS, Ubuntu, Debian, and Fedora. Many of my Docker Hub images for Ansible testing include systemd so I can test services that are installed inside. For the most part, systemd-related issues are rare, but it seems with Fedora and DNF, I often encounter random test failures which invariably have an error message like:
No such file or directory: '/var/lib/dnf/rpmdb_lock.pid'
The full Ansible traceback is: