fanctl

Automatic PID fan control for remote IPMI on Debian with Supermicro X9DRi-LN4F+

Why

For automatically monitoring the two-zone CPU/Peripheral fan controller on a Supermicro X9DRi-LN4F using remote IPMI. Works well from a VM running on this host.

How

In my setup, the peripheral zone controls a 140mm fan wall mounted in front of the hotswap drive bays of an SC836 3u 16-bay chassis. The CPU zone controls the CPU fans, rear case fans, and a 120mm fan mounted on the rear of the chassis behind the HBA cards to pull air through their heatsinks.

To deploy

• clone this repo into somewhere reasonable (I used /opt/fanctl)
• (optional) set up a .env file to override tuning parameters and logging so you don't have to edit the scripts to do so. read the scripts for tunable params
• (optional if you don't use ZFS) edit the spinpid2z.service unit and remove the dependency on zfs.service. I added that dependency to make sure my logs land properly.
• sudo ln -s /opt/fanctl/spinpid2z.service /etc/systemd/system/spinpid2z.service
• sudo systemctl enable spinpid2z
• sudo systemctl start spinpid2z

Equipment

• Front fan wall: Noctua NF-A14 IndustrialPPC-3000 PWM x 3, arranged three wide to blow directly into the drive bays, with a PWM splitter wire running through the front IO panel into the chassis.
• Rear PCI-e fan: Noctua NF-F12 IndustrialPPC-3000 PWM x 1, snug fit in the expansion card area on the rear exterior of the chassis, with the cable running through a perforated expansion slot shield into the chassis.
• Interior fan wall: Noctua NF-A8 PWM x 3
• Rear chassis fans: Noctua NF-A8 PWM x 2
• CPU coolers: Noctua NH-D9DX i4 3U x 2. Since the SC836 is a 3U server, decided to play it safe and get a cooler explicitly rated for 3U chassis compatibility.
• All 16 bays populated

Results

Temperatures

At idle, with a 24℃ ambient temperature, this setup keeps average drive temperatures around the temperature set point (37C as of writing) with ~40-60% duty cycle with average workloads.

Noise levels

According to the NIOSH SLM app on my phone, the ambient noise level of my apartment is ~34 dB(A). When measured 3 feet from the server cabinet, at the entry to my closet, I measured these figures using spintest:

Combined duty cycle	Noise (in dB(A))
100%	56
90%	55
80%	53
70%	49
60%	45.7
50%	42.6
40%	38
30%	34.5

Since the cabinet is in a closet with an open doorway, the noise is only audible in the adjacent room if the duty cycle is above 60%, or above 40% when standing in front of it.

Inspirations

• Largely based on https://www.truenas.com/community/threads/fan-scripts-for-supermicro-boards-using-pid-logic.51054/page-13#post-551335, with modifications:
  • made it work under Debian (original was intended for FreeBSD)
  • portability with .env file
  • remote IPMI
  • service for systemctl
  • shellcheck and formatting
• https://www.youtube.com/embed/0UjyL6ZiMkI