Supermicro X10 Fan Control for TrueNAS Scale

Overview

This script provides dynamic fan control for Supermicro X10 motherboards on TrueNAS Scale, using IPMI raw commands to adjust fan speeds based on CPU and disk temperatures.

Features:

• Linear fan curve from 50% (idle) to 100% (max temp)
• Monitors both CPU and disk temperatures
• Hysteresis to prevent fan speed oscillation
• Runs as a systemd service
• Logging with automatic rotation

Temperature Curves

Component	Min Temp	Max Temp	Fan Response
CPU	40°C	70°C	50% → 100%
Disk	35°C	50°C	50% → 100%

The script uses whichever source requires higher fan speed.

Installation on TrueNAS Scale

Important: TrueNAS Scale Persistence

TrueNAS Scale is based on an immutable root filesystem. Changes to most system directories are lost on reboot. To persist custom scripts, use one of these approaches:

Option 1: Init/Shutdown Scripts (Recommended)

1. Copy the script to a dataset that persists:

   # Create a scripts directory on your pool
   mkdir -p /mnt/your-pool/scripts
   cp supermicro_fan_control.sh /mnt/your-pool/scripts/
   chmod +x /mnt/your-pool/scripts/supermicro_fan_control.sh

2. In TrueNAS Web UI:

   • Go to System → Advanced → Init/Shutdown Scripts
   • Click Add
   • Set:
     • Description: Fan Control
     • Type: Command
     • Script: /usr/bin/bash /mnt/your-pool/scripts/supermicro_fan_control.sh --daemon &
     • When: Post Init

Option 2: Cron Job with Frequent Polling

If you prefer not to run a daemon, use cron to run the script periodically:

1. Copy script to persistent storage:

   mkdir -p /mnt/your-pool/scripts
   cp supermicro_fan_control.sh /mnt/your-pool/scripts/
   chmod +x /mnt/your-pool/scripts/supermicro_fan_control.sh

2. In TrueNAS Web UI:

   • Go to System → Advanced → Cron Jobs
   • Click Add
   • Set:
     • Description: Fan Control
     • Command: /usr/bin/bash /mnt/your-pool/scripts/supermicro_fan_control.sh
     • Run As User: root
     • Schedule: Every minute (*/1 in the minute field)

Option 3: Systemd Service (Requires Re-setup After Updates)

This method provides the cleanest daemon operation but requires re-running after TrueNAS updates:

# Copy files
cp supermicro_fan_control.sh /usr/local/bin/
chmod +x /usr/local/bin/supermicro_fan_control.sh
cp supermicro-fan-control.service /etc/systemd/system/

# Enable and start
systemctl daemon-reload
systemctl enable supermicro-fan-control.service
systemctl start supermicro-fan-control.service

# Check status
systemctl status supermicro-fan-control.service
journalctl -u supermicro-fan-control.service -f

Configuration

Edit the script to adjust these variables at the top:

# Fan speed limits (percentage)
MIN_FAN_SPEED=50      # Minimum fan speed
MAX_FAN_SPEED=100     # Maximum fan speed

# CPU temperature thresholds (Celsius)
CPU_TEMP_MIN=40       # Below this = MIN_FAN_SPEED
CPU_TEMP_MAX=70       # At or above = MAX_FAN_SPEED

# Disk temperature thresholds (Celsius)
DISK_TEMP_MIN=35      # Below this = MIN_FAN_SPEED
DISK_TEMP_MAX=50      # At or above = MAX_FAN_SPEED

# Polling interval for daemon mode (seconds)
POLL_INTERVAL=30

Usage

# Single run (test mode)
./supermicro_fan_control.sh

# Show current temperatures and fan speeds
./supermicro_fan_control.sh --status

# Run as daemon
./supermicro_fan_control.sh --daemon

Verifying IPMI Access

Before running, verify IPMI is working:

# Check CPU temperature sensors
ipmitool sdr type Temperature

# Check current fan speeds
ipmitool sdr type Fan

# Test manual fan control (set to 60%)
ipmitool raw 0x30 0x45 0x01 0x01           # Set to Full/Manual mode
ipmitool raw 0x30 0x70 0x66 0x01 0x00 0x3c # Set zone 0 to 60%
ipmitool raw 0x30 0x70 0x66 0x01 0x01 0x3c # Set zone 1 to 60%

Troubleshooting

"Could not read CPU temperature"

The script tries multiple sensor names. Check what your board reports:

ipmitool sdr type Temperature

Then update the sensor names in the get_cpu_temp() function if needed.

Fans not responding

1. Verify your board supports the raw commands:

   # Check if board is in manual mode
   ipmitool raw 0x30 0x45 0x00

2. Some X10 variants use different zone mappings. Check Supermicro documentation for your specific board model.

Permission denied

Ensure the script runs as root:

sudo ./supermicro_fan_control.sh --status

Tested Boards

• X10SL7-F
• X10SLM-F
• X10SLL-F
• X10DRL-i
• X10SRi-F

Other X10 boards should work but may need sensor name adjustments.

Safety Notes

• The script enforces a 50% minimum fan speed to prevent thermal issues
• If the script crashes, fans will remain at their last set speed
• Consider setting BIOS fan control to "Optimal" as a fallback
• Monitor temperatures for the first few days after deployment

Log Location

Logs are written to: /var/log/fan_control.log

View recent activity:

tail -f /var/log/fan_control.log