Daemon to set the Lincstation N2 LEDs on Linux other than Unraid

The Lincstation N2 is a fine all-flash NAS. It uses mostly standard PC hardware, which means you can run your own OS on top of it instead of proprietary ones like QNAP's QuTS Hero or Synology's whatever (if you weren't deterred by Synology's abbhorent moves to force you to buy their marked-up hard drives).

I installed Alpine Linux on mine. Unfortunately, if you do not use the supplied freemium Unraid software, the LEDs will blink continuously, which is particularly annoying in my case because they are in my peripheral vision.

Lincstation supplies a closed-source daemon with its Unraid distribution on a USB stick (I removed mine), apparently written in Go but quite inefficient because it makes the necessary I2C/SMBus calls to the LEDs by forking to the i2c-tools utility i2cset. Github user ffalt reverse-engineered the protocol in this gist.

I asked the Anthropic Claude Sonnet 4 LLM to help me write a daemon written in C to manage the LEDs: https://claude.ai/public/artifacts/cc0feaf6-524f-431b-b1e8-505ad07f75f3

Claude did a surprisingly decent job of writing the boilerplate, you can see in the Git history the changes I did to make it work properly, including subtle bugs around handling rollover or incorrectly thinking disk I/O utilization is 100% when no disk writes occurred.

I have only tested this on Alpine Linux but there is no reason it shouldn't work on other flavors of Linux (you may need to make changes for systemd, though).

To build, simply run make. You will need to have the packages i2c-tools and i2c-tools-dev (and optionally i2c-tools-doc) installed.

You can activate debug output on stdout by calling:

env LEDS_DEBUG=true lincstation_leds

By default, it will update the LEDs once per second. If you want something more real-time, you can change ACTIVITY_SAMPLE_INTERVAL in the code to something shorter. Just be aware that at 10 Hz, it consumes 2–3% CPU on mine.