Use Corsair Commander Core on TrueNAS with liquidctl to Control Fans

Before we start, here's exactly what I'm working with for this article:

• Corsair iCUE H115i Elite Capellix RGB V2 280mm Water Cooling Kit
• Corsair Commander Core
• TrueNAS SCALE 22.02.1
• liquidctl v1.11.0.dev2+g9b058ba

I recently wanted to add some more cooling to my NAS.  I had some Lian Li controllable fans laying around and I picked up a Corsair H115i AIO cooler at Micro Center.  The H115i comes with a Commander Core which can control the AIO's fans and the Lian Li fans (fan control only - no RGB; it's a NAS so I don't care about the RGB aspect).

The Commander Core interfaces via USB 2.0 header.  Upon first boot, everything looked fine.  I, however, wanted to be able to control these fans - even if manually.  TrueNAS SCALE 22.02.1 doesn't have any fan control yet so I decided to do some research and stumbled upon liquidctl.

liquidctl is a beautiful open source codebase used for Windows, Linux, and macOS distros to manage fan controllers and AIOs.  Unfortunately, the Commander Core wasn't supported out-of-the-box on the latest release (as of June 7, 2022).  However, to my happiness, it was supported (albeit experimental) on the latest dev release (1.11.0.dev2+g9b058ba).  Here's how to use it on TrueNAS!

Installation

Installation is easy.  We already have Python installed so it's a breeze:

python -m pip install git+https://github.com/liquidctl/liquidctl#egg=liquidctl

That's it!

Usage

1. Let's initialize our hardware:
   liquidctl initialize all
2. If successful, you should be able to check the status of your fans now and temps:
   liquidctl status
3. If you want to manually set your fan speed to 100%, for example, you can run:
   liquidctl set fans speed 100

More documentation on this can be found onliquidctl's GitHub page.

Auto Start at Boot

If you want, you can initialize liquidctl at boot. You can also set your fans to whatever speed or color you want at this time. We do this by creating a new oneshot systemd service.

1. Create a new service file at:
   /etc/systemd/system/liquidcfg.service
2. Fill it with this content. Tweak to your liking. 

   [Unit]
   Description=AIO startup service
   
   [Service]
   Type=oneshot
   ExecStart=liquidctl initialize all
   
   [Install]
   WantedBy=default.target

3. Reload:
   systemctl daemon-reload
4. Enable it for next boot:
   systemctl enable liquidcfg
5. Start it now:
   systemctl start liquidcfg