Dell Server Fan Controller

Bash script / service to control fan speeds in Dell servers (Mainly 11th gen)

Summary

• Simple bash script with minimum requirements (ipmitool and lm-sensors)
• Has temperature averaging and sudden-change-prevention
• Tested on Debian / Proxmox
• Can be run manually/once-off for when the server's on a workbench, or setup as systemd service.

Failsafe / Testing

• When testing for the first time, manually run outside of systemd and issue a Ctrl+C (sig-int) if it doesn't work as expected.
• This will stop the script and set the dell server back to auto fan controll.

Requirements

This script only needs 2 things to work, fan control and temperatures.

apt install ipmitool ipmitool, utility for IPMI control with kernel driver or LAN interface (daemon)

apt install lm-sensors lm-sensors, utilities to read temperature/voltage/fan sensors

Installation

Option A - run the script as a once-off

• chmod +x dell_server_fan_controller.sh
• Make sure to check the bash location at the top of the script matches env
• ./dell_server_fan_controller.sh

Option B - run the script as a service

• Choose a home for the script
• Configure systemd to run it

Example systemd configuration file: /etc/systemd/system/fancontroller.service

[Unit]
Description=Dell Server IPMI Fan Controller
After=multi-user.target

[Service]
ExecStart=/usr/local/scripts/dell_server_fan_controller.sh
ExecStop=/bin/kill -s 2 $MAINPID

[Install]
WantedBy=multi-user.target

ToDo

• Vary fan control from ranges instead of fixed values for smoother changes.
• Test on 12th and 13th generation Dells (not that they really need it, their controllers as much more tame).