Recent Blog Posts

The Raspberry Pi 4 might not need a fan anymore

tl;dr: After the fall 2019 firmware/bootloader update, the Raspberry Pi 4 can run without throttling inside a case—but only just barely. On the other extreme, the ICE Tower by S2Pi lives up to its name.

Raspberry Pi 4 cooling options including ICE tower cooling fan and a case mod fan
Three options for keeping the Pi 4 cozy: unmodified Pi 4 case, modded case with fan, and the ICE Tower.

A few months ago, I was excited to work on upgrading some of my Raspberry Pi projects to the Raspberry Pi 4; but I found that for the first time, it was necessary to use a fan to actively cool the Pi if used in a case.

Two recent developments prompted me to re-test the Raspberry Pi 4's thermal properties:

If you're having trouble formatting a new SSD in a Mac, it could be the cable

tl;dr: If you see weird errors when using or formatting a drive internally on a Mac (especially after upgrading to a newer and/or faster SATA hard drive), it could mean the SATA cable needs to be replaced.

Mac mini mid-2011 lower SATA hard drive cable with connector
Who would've thought such a tiny cable could cause so many problems?

I have an older Mac mini (mid-2011 i5 model), and I use it as a general media server and network backup. It handles Time Machine backups for two other Macs, it has about 20 TB of external storage connected, and I also use it as a 'home base' to store all my Dropbox, iCloud, and Photos content locally, and store an extra Time Machine backup of all that. I'm a little nutty about backups... but I haven't lost a file in two decades and I don't want to start now ;-).

Sponsor my Open Source development work on GitHub

tl;dr: You can now sponsor my open source development work via GitHub Sponsors.

GitHub sponsors geerlingguy

GitHub Sponsors is the latest foray into building a more sustainable future for open source software development. There have been many attempts before, a few of which I tried (Gratipay, Patreon, etc.), but most of them never reached a critical mass, and at most you'd end up getting maybe $20-50/month out of the platform. Another prolific open source contributor I've long followed wrote about the topic of open source support and developer burnout in a post this year, Webform, Drupal, and Open Source...Where are we going?.

Limiting disk iops on a larger Munin server using rrdcached

I've long used Munin for basic resource monitoring on a huge variety of servers. It's simple, reliable, easy to configure, and besides the fact that it uses Perl for plugins, there's not much against it!

Last week, I got a notice from my 'low end box' VPS provider that my Munin server—which is aggregating data from about 50 other servers—had high IOPS and would be shut down if I didn't get it back into an allowed threshold. Most low end VPSes run things like static HTML websites, so disk IO is very low on average. I checked my Munin instance, and sure enough, it was constantly churning through around 50 iops. For a low end server, this can cause high iowait for other tenants of the same server, so I can understand why hosting providers don't want applications on their shared servers doing a lot of constant disk I/O.

Using iotop, I could see the munin-update processes were spending a lot of time writing to disk. And munin's own diskstats_iops plugin showed the same:

Rescue photos and other files from an SD or microSD card with PhotoRec

As a photographer who's taken and processed at least 200,000 photos in the past couple decades, you'd think I have a solid workflow that results in zero lost files... but you'd be wrong. 99% of the time, I follow the workflow:

  1. Import photos from memory card.
  2. Make sure backup of imported photos completes (so I have two local copies—I also have one copy back up to a cloud storage provider, so two local and one cloud backup).
  3. Format the memory card.

A lot of photographers shoot with two memory cards, and have photos written to both—that way the 2nd card would be a double-failsafe. But for most jobs, I don't do that. And one of my digital cameras doesn't even have two memory card slots, so this isn't an option!

Anyways, more often than I'd like to admit, I do something dumb, like:

Molecule fails on converge and says test instance was already 'created' and 'prepared'

I hit this problem every once in a while; basically, I run molecule test or molecule converge (in this case it was for a Kubernetes Operator I was building with Ansible), and it says the instance is already created/prepared—even though it is not—and then Molecule fails on the 'Gathering Facts' portion of the converge step:


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