Monitor disk temperature of disks passed through to a VM, so that you can contol fan speed according to that temp from the host (Proxmox, etc.)

I use it to control fan speed of my Proxmox server based on the temperature of the HDD disk on a SATA Controller that is passed through into a VM (it is Unraid in my case).

This project uses a DKMS module to fake a virtual temperature sensor on the host, which can then be read by lm-sensors and used to control fan speed.

Inside the VM, it uses a script to read the disk temperature calculate the disk's max temperature and can be collected by the host via qemu-guest-agent. The host system then collects this information and updates the virtual sensor using a systemd timer. Important Note: this script won't wake up the disk, so if all the disks are idle, the temperature will be reported as 0°C.

• A VM with a disk controller passed through (e.g., SATA controller).
• A disk attached to that controller.
• A Linux-based VM (e.g., Unraid, Ubuntu, etc.) with the necessary tools installed.
• A host system that supports DKMS (e.g., Proxmox, Ubuntu, etc.).

1. Clone the repository:

   git clone https://github.com/wxxsfxyzm/hdd-temp-monitor.git
   cd hdd-temp-monitor

2. Install the required packages:

   sudo apt update
   sudo apt install -y \
       build-essential \
       linux-headers-$(uname -r) \
       dkms \
       lm-sensors \
       fancontrol \
       jq

3. Copy the DKMS module to the appropriate directory:

   sudo cp -r virt-temp/virt-temp-1.0 /usr/src/

4. Register the DKMS module:

   sudo dkms add -m virt-temp -v 1.0

5. Build and install the DKMS module:

   sudo dkms build -m virt-temp -v 1.0
   sudo dkms install -m virt-temp -v 1.0

6. Load the module:

   sudo modprobe virt-temp

7. Verify that the module is loaded through dmesg:

   dmesg | grep virt-temp

   if you see output indicating that the module is loaded

   [    3.123456] virt-temp: device registered

   it means the installation was successful.

8. Configure sensors to read the temperature:

   • Run the script below to create a configuration file for the sensors, so that sensors can read the temperature from the virtual disk:

   echo -e 'chip "virt_temp-*"\n    label temp1 "HDD Max"' | sudo tee /etc/sensors.d/virt-temp.conf

   after that let sensors reload the configuration:

   sensors -s

   if you see no error, it means the configuration is successful.

9. Verify that the module is loaded and the temperature is being read:

   sensors

   You should see an output similar to:

   virt_temp-virtual-0
   Adapter: Virtual device
   HDD Max:       +0.0°C
   

   This indicates that the temperature sensor is working correctly.

10. Configure the module to load at boot:

    echo "virt-temp" | sudo tee /etc/modules-load.d/virt-temp.conf

1. Ensure that the VM has necessary permissions to access the disk controller and temperature sensors.

   • For Unraid, it works out of the box as long as the disk controller is passed through correctly.

2. Unraid runs it's system in memory, so you'd better put scripts you need into /boot/config folder to avoid losing them after reboot.

   • In my case, I put them in /boot/config/extras folder, you can create this folder if it does not exist:

   mkdir -p /boot/config/extras

3. Upload two scripts in vm/unraid folder to your Unraid VM's /boot/config/extras folder (you can put them elsewhere, but remember to change the paths in the scripts accordingly):

   • hdd-temp-monitor.sh: This script will read the disk temperature and output it, it also have some other options:

   Usage: bash hdd_temp_monitor.sh [OPTIONS]
   Monitor disk temperatures and output maximum value
   
   Options:
     -t, --type [default|unraid]  Disk type context (default: default)
         default: include sda in monitoring
         unraid:  skip monitoring sda
     -i, --info [short|full]       Output information level (default: short)
         short: output only maximum temperature
         full:  output detailed disk information
     -h, --help                    Show this help message

   • report_temp.sh: boot partition is FAT32, which does not support Linux ACLs, and qemu-guest-agent does not support executing script with options inside a VM, so you need a wrapper script to run hdd-temp-monitor.sh with options, this script will be executed by qemu-guest-agent to report the temperature to the host.

4. remember to enable qemu-guest-agent in your /boot/config/go file, add the following line before the last line /usr/local/sbin/emhttp:

   # Start qemu-ga
   /usr/bin/qemu-ga -l /tmp/qemu-ga.log -d

   a reboot is required for Unraid to apply the changes.

Other Linux-based VMs (like Ubuntu) can use the hdd-temp-monitor.sh script directly without the need for a wrapper script, just make sure to set the executable permission:

chmod +x hdd-temp-monitor.sh

Remember to install qemu-guest-agent and smartmontools if they are not already installed in your VM.

1. Create a script on the host to fetch the disk temperature from the VM and update it in the host's sensors:

   sudo cp host/proxmox/virt-sensor-collector.sh /usr/local/bin/
   sudo chmod +x /usr/local/bin/virt-sensor-collector.sh

2. Create a systemd timer to run the script periodically:

   # /etc/systemd/system/hdd-temp.service
   [Unit]
   Description=Update Virtual HDD Temperature
   
   [Service]
   ExecStart=/usr/local/bin/virt-sensor-collector.sh

   # /etc/systemd/system/hdd-temp.timer
   [Unit]
   Description=Update HDD temp every 5 seconds
   
   [Timer]
   OnBootSec=5s
   OnUnitActiveSec=5s
   AccuracySec=1ms
   
   [Install]
   WantedBy=timers.target

3. Enable and start the timer:

   sudo systemctl daemon-reload
   sudo systemctl enable hdd-temp.timer
   sudo systemctl start hdd-temp.timer

4. Verify that the timer is running:

   systemctl status hdd-temp.timer

5. Check the disk temperature on the host:

   sensors

After following these steps, you should see the disk temperature being reported correctly on the host system.

1. Configure fancontrol:

   • Edit the fancontrol configuration file:

     sudo nano /etc/fancontrol

   • Set the appropriate parameters for your system. You can use the pwmconfig utility to help generate a basic configuration.

   • Start the fancontrol service:

     sudo systemctl start fancontrol
     sudo systemctl enable fancontrol

2. Monitor the disk temperature and fan speed:

   • You can use the sensors command to check the disk temperature.
   • The fan speed will be controlled automatically based on the temperature readings.