Super Micro fan control for Linux (home) servers.
This is a systemd service
running on Linux and is able to control fans in CPU and HD zones with the help of IPMI on Super Micro X10-X13 (and some X9) motherboards.
You can also run smfc
in docker, see more details in Docker.md.
systemd
packagecoretemp
kernel module for Intel(R) CPUsk10temp
kernel module for AMD(R) CPUsdrivetemp
kernel module (kernel version 5.6+ required) modules for SATA hard disksbash
ipmitool
smartmontools
for the standby guard featurehddtemp
for the SAS/SCSI disksipmi/set_ipmi_threshold.sh
). coretemp/k10temp
and drivetemp
).install.sh
./opt/smfc/smfc.conf
and command line options in /etc/default/smfc
.systemd
serviceThis service was planned for Super Micro motherboards installed in computer chassis with two independent cooling systems employing separate fans. In IPMI terms these are called:
Please note: the fan assignment to zones is predefined in IPMI, and it cannot be changed! On the other hand smfc
implements a feature, called Swapped zones, in order to make the use of the fans more suitable.
In this service a fan control logic is implemented for both zones which can:
The fan control logic can be enabled and disabled independently per zone. In the zone all fans will have the same rotational speed. The user can configure different temperature calculation method (e.g. minimum, average, maximum temperatures) in case of multiple heat sources in a zone.
Please note that smfc
will set all fans back to 100% speed at service termination in order to avoid overheating!
The user-defined parameters (see configuration file below for more details) create a function where a temperature interval is being mapped to a fan level interval.
The following five parameters will define the function in both zones:
min_temp=
max_temp=
min_level=
max_level=
steps=
With the help of this function smfc
can map any new temperature measurement value to a fan level. Changing the fan rotational speed is a very slow process (i.e. it could take seconds depending on fan type and the requested amount of change), so we try to minimize these kinds of actions. Instead of setting fan rotational speed continuously we define discrete fan levels based on steps=
parameter.
In order to avoid/minimize the unnecessary change of fan levels the service employs the following steps:
[IPMI] fan_level_delay=
in order to let the fan implement the physical change.sensitivity=
) for the fan control logic. If the temperature change is below this value then the service will not react at all. polling=
defines the frequency of reading zone's temperature. The bigger polling time in a zone the lower frequency of fan speed change.In some cases it is useful to swap IPMI zones. In this way the fans FAN1, FAN2, ...
will cool the HD zone and the fans FANA, FANB, ...
will cool the CPU zone. This feature could be useful if you need more fans for the HD zone since Super Micro motherboards have more fan connectors in the CPU zone usually. This feature can be enabled with [IPMI] swapped_zones=True
configuration parameter, in default it is disabled.
For HD zone an additional optional feature was implemented, called Standby guard, with the following assumptions:
This feature is monitoring the power state of SATA hard disks (with the help of the smartctl
) and will put the whole array to standby mode if a few members are already stepped into that. With this feature we can avoid a situation where the array is partially in standby mode while other members are still active.
The smfc
service was originally designed for SATA
hard drives, but from 3.0
version it is also compatible with NVME
and SAS/SCSI
disks. The following table summarizes how the temperature is read for different disk types:
Disk type | Temperature source | Kernel module | Command |
---|---|---|---|
SATA |
Linux kernel (HWMON) | drivetemp |
- |
NVME |
Linux kernel (HWMON) | - | - |
SAS/SCSI |
hddtemp |
- | hddtemp |
Some additional notes:
NVME
SSDs no kernel driver will be loaded the kernel itself can handle this disk typeSATA
disks the drivetemp
kernel module should be loaded (this is the fastest way to read disk temperature and the kernel module can report the temperature during sleep mode!)SAS/SCSI
disks the hddtemp
command will be used to read disk temperature (NO daemon mode is required for hddtemp
!)hd_names=
configuration parameter but the power management (standy mode) and Standby guard feature will not be supported in this case.smfc
can handle NVME SSDs, it is NOT RECOMMENDED to include NVME disks in hd_names=
parameters, because the hard disks and NVME SSDs are operating in quite different temperature zones (e.g. 40 C vs 70 C).ata-
/-SATA
, nvme-
and scsi-
)Originally this software was designed to work with Super Micro X10 and X11 motherboards with a BMC chip (i.e. ASPEED AST2400/2500) and IPMI functionality.
In case of X9 motherboards the compatibility is not guaranteed, it depends on the hardware components of the motherboard (i.e. not all X9 motherboards employ BMC chip).
The earlier X8 motherboards are NOT compatible with this software. They do not implement IPMI_FULL
mode, and they cannot control fan levels how it is implemented in smfc
.
X13 motherboards (with AST2600 BMC chips) seem to be compatible with smfc (see mode details in issue #33 about an X13SAE-F motherboard).
Fan control and IPMI_FULL
mode are working properly. The only difference is in using thresholds, AST2600 implements only Lower Critical
threshold, so setting up thresholds is different in this case.
Feel free to create a short feedback in issue #19 on your compatibility experience.
IPMI uses six sensor thresholds to specify the safe and unsafe fan rotational speed intervals (these are RPM values rounded to nearest hundreds, defined for each fan separately):
Lower Non-Recoverable
Lower Critical
Lower Non-Critical
Upper Non-Critical
Upper Critical
Upper Non-Recoverable
Like many other utilities (created by NAS and home server community), smfc
also uses IPMI FULL mode for fan control, where all fans in the zone:
[Lower Critical, Upper Critical]
intervalLower Critical
or Upper Critical
threshold then IPMI will generate an assertion event and will set the all fan speeds back to 100% in the zonePlease also consider the fact that fans are mechanical devices, their rotational speed is not stable (it could be fluctuating). In order to avoid IPMI's assertion mechanism described here please follow the next steps:
min_level
/max_level
values for smfc
respecting the variance of the all fans in the IPMI zone (it could take several iterations and adjustments) Here is a real-life example for a Noctua NF-F12 PWM fan:
Upper Non-Recoverable = 1800 rpm
Upper Critical = 1700 rpm
Upper Non-Critical = 1600 rpm
Lower Non-Critical = 200 rpm
Lower Critical = 100 rpm
Lower Non-Recoverable = 0 rpm
Max RPM = 1500 rpm
Min PRM = 300 rpm
max_level = 100 (i.e. 1500 rpm)
min_level = 35 (i.e. 500 rpm)
Notes:
ipmitool
command to display the current IMPI sensor thresholds for fans:
root@home:~# ipmitool sensor|grep FAN
FAN1 | 500.000 | RPM | ok | 0.000 | 100.000 | 200.000 | 1600.000 | 1700.000 | 1800.000
FAN2 | 500.000 | RPM | ok | 0.000 | 100.000 | 200.000 | 1600.000 | 1700.000 | 1800.000
FAN3 | na | | na | na | na | na | na | na | na
FAN4 | 400.000 | RPM | ok | 0.000 | 100.000 | 200.000 | 1600.000 | 1700.000 | 1800.000
FANA | 500.000 | RPM | ok | 0.000 | 100.000 | 200.000 | 1600.000 | 1700.000 | 1800.000
FANB | 500.000 | RPM | ok | 0.000 | 100.000 | 200.000 | 1600.000 | 1700.000 | 1800.000
ipmitool
command to list assertion events:
root@home:~# ipmitool sel list
1 | 10/19/2023 | 05:15:35 PM CEST | Fan #0x46 | Lower Critical going low | Asserted
2 | 10/19/2023 | 05:15:35 PM CEST | Fan #0x46 | Lower Non-recoverable going low | Asserted
3 | 10/19/2023 | 05:15:38 PM CEST | Fan #0x46 | Lower Non-recoverable going low | Deasserted
4 | 10/19/2023 | 05:15:38 PM CEST | Fan #0x46 | Lower Critical going low | Deasserted
5 | 10/19/2023 | 05:20:59 PM CEST | Fan #0x46 | Lower Critical going low | Asserted
ipmitool
commands to specify all six sensor thresholds for FAN1:
root@home:~# ipmitool sensor thresh FAN1 lower 0 100 200
root@home:~# ipmitool sensor thresh FAN1 upper 1600 1700 1800
ipmi/set_ipmi_treshold.sh
to configure all IPMI sensor thresholdsipmitool sensors
, you may want to reset the BMC to factory default using the Web UI or using ipmitool mc reset cold
Noctua specifies the variance of minimum and maximum fan rotational speeds (e.g. see the specification of Noctua NF-F12 PWM). For example:
Rotational speed (+/- 10%) 1500 RPM
: 1350-1650 RPM intervalMin. rotational speed @ 20% PWM (+/-20%) 300 RPM
: 240-360 RPM intervalPlease note that LNA/ULNA cables or Y-cables can modify the rotational speed calculations here and the required IPMI sensor thresholds too.
You can read more about:
If low noise and low heat generation are important attributes of your Linux box, then you may consider the following chapters.
Most of the modern CPUs has multiple energy saving features. You can check your BIOS and enable them in order to minimize the heat generation.
Intel(R) CPUs:
AMD(R) CPUs:
With this setup the CPU will change its base frequency and power consumption dynamically based on the load.
In case of SATA hard disks, you may enable:
With the help of command hdparm
you can enable advanced power management and specify a spin down timer (read more here):
hdparm -B 127 /dev/sda
hdparm -S 240 /dev/sda
In file /etc/hdparm.conf
you can specify all parameters in a persistent way:
quiet
/dev/sda {
apm = 127
spindown_time = 240
}
/dev/sdb {
apm = 127
spindown_time = 240
}
...
Important notes:
[HD zone] polling=
minimum twice bigger as the spindown_time
specified here./etc/hdparm.conf
you must define HD names in /dev/disk/by-id/...
form to avoid inconsistency.We need to load the following important Linux kernel modules:
coretemp
: temperature report for Intel(R) CPUsk10temp
: temperature report for AMD(R) CPUsdrivetemp
: temperature report for SATA hard disks (available from kernel 5.6+ version)Use /etc/modules
file for persistent loading of these modules.
Here are some sample HWMON file locations for these kernel modules:
coretemp
: /sys/devices/platform/coretemp.0/hwmon/hwmon*/temp1_input
k10temp
: /sys/bus/pci/drivers/k10temp/0000*/hwmon/hwmon*/temp1_input
drivetemp
: /sys/class/scsi_disk/0:0:0:0/device/hwmon/hwmon*/temp1_input
Notes:
smfc
is able to find the proper HWMON file automatically for Intel(R) CPUs and SATA hard drives, but users of the AMD(R) CPU should specify manually (see hwmon_path=
parameter in the config file)drivetemp
module is the fastest way to get the temperature of the hard disks, and it can read temperature of the SATA hard disks even in standby mode, too. For the installation you need a root user. The default installation script install.sh
will use the following folders:
File | Installation folder | Description |
---|---|---|
smsc.service |
/etc/systemd/system |
systemd service definition file |
smsc |
/etc/default |
service command line options |
smsc.py |
/opt/smfc |
service (python program) |
smsc.conf |
/opt/smfc |
service configuration file |
but you can use freely any other folders too. The service has the following command line options:
root@home:~/opt/smfc# ./smfc.py --help
usage: smfc.py [-h] [-c CONFIG_FILE] [-v] [-l {0,1,2,3,4}] [-o {0,1,2}]
optional arguments:
-h, --help show this help message and exit
-c CONFIG_FILE configuration file
-v show program's version number and exit
-l {0,1,2,3,4} log level: 0-NONE, 1-ERROR(default), 2-CONFIG, 3-INFO, 4-DEBUG
-o {0,1,2} log output: 0-stdout, 1-stderr, 2-syslog(default)
You may configure logging output and logging level here and these options can be specified in /etc/default/smfc
in a persistent way.
Edit /opt/smfc/smfc.conf
and specify your configuration parameters here:
#
# smfc.conf
# smfc service configuration parameters
#
[Ipmi]
# Path for ipmitool (str, default=/usr/bin/ipmitool)
command=/usr/bin/ipmitool
# Delay time after changing IPMI fan mode (int, seconds, default=10)
fan_mode_delay=10
# Delay time after changing IPMI fan level (int, seconds, default=2)
fan_level_delay=2
# CPU and HD zones are swapped (bool, default=0).
swapped_zones=0
[CPU zone]
# Fan controller enabled (bool, default=0)
enabled=1
# Number of CPUs (int, default=1)
count=1
# Calculation method for CPU temperatures (int, [0-minimum, 1-average, 2-maximum], default=1)
temp_calc=1
# Discrete steps in mapping of temperatures to fan level (int, default=6)
steps=6
# Threshold in temperature change before the fan controller reacts (float, C, default=3.0)
sensitivity=3.0
# Polling time interval for reading temperature (int, sec, default=2)
polling=2
# Minimum CPU temperature (float, C, default=30.0)
min_temp=30.0
# Maximum CPU temperature (float, C, default=60.0)
max_temp=60.0
# Minimum CPU fan level (int, %, default=35)
min_level=35
# Maximum CPU fan level (int, %, default=100)
max_level=100
# Optional parameter, it will be generated automatically for Intel CPUs and must be specified manually for AMD CPUs.
# Path for CPU sys/hwmon file(s) (str multi-line list, default=/sys/devices/platform/coretemp.0/hwmon/hwmon*/temp1_input)
# hwmon_path=/sys/devices/platform/coretemp.0/hwmon/hwmon*/temp1_input
# /sys/devices/platform/coretemp.1/hwmon/hwmon*/temp1_input
# or
# hwmon_path=/sys/bus/pci/drivers/k10temp/0000*/hwmon/hwmon*/temp1_input
[HD zone]
# Fan controller enabled (bool, default=0)
enabled=1
# Number of HDs (int, default=1)
count=1
# Calculation of HD temperatures (int, [0-minimum, 1-average, 2-maximum], default=1)
temp_calc=1
# Discrete steps in mapping of temperatures to fan level (int, default=4)
steps=4
# Threshold in temperature change before the fan controller reacts (float, C, default=2.0)
sensitivity=2.0
# Polling interval for reading temperature (int, sec, default=10)
polling=10
# Minimum HD temperature (float, C, default=32.0)
min_temp=32.0
# Maximum HD temperature (float, C, default=46.0)
max_temp=46.0
# Minimum HD fan level (int, %, default=35)
min_level=35
# Maximum HD fan level (int, %, default=100)
max_level=100
# Names of the HDs (str multi-line list, default=)
# These names MUST BE specified in '/dev/disk/by-id/...' form!
hd_names=
# Optional parameter, it will be generated automatically based on the disk names.
# List of files in /sys/hwmon file system or 'hddtemp' (str multi-line list, default=)
# hwmon_path=/sys/class/scsi_disk/0:0:0:0/device/hwmon/hwmon*/temp1_input
# /sys/class/scsi_disk/1:0:0:0/device/hwmon/hwmon*/temp1_input
# hddtemp
# Standby guard feature for RAID arrays (bool, default=0)
standby_guard_enabled=0
# Number of HDs already in STANDBY state before the full RAID array will be forced to it (int, default=1)
standby_hd_limit=1
# Path for 'smartctl' command (str, default=/usr/sbin/smartctl).
# Required for 'standby guard' feature only
smartctl_path=/usr/sbin/smartctl
# Path for 'hddtemp' command (str, default=/usr/sbin/hddtemp).
# Required for reading of the temperature of SAS/SCSI disks.
hddtemp_path=/usr/sbin/hddtemp
Important notes:
[HD zone} hd_names=
: This is a compulsory parameter, its value must be specified in /dev/disk/by-id/...
form (the /dev/sda
form is not persistent could be changed after a reboot).
[CPU zone] / [HD zone] min_level= / max_level=
: Check the stability of your fans and adjust the fan levels based on your measurement. As it was stated earlier, IPMI can switch back to full rotational speed if fans reach specific thresholds. You can collect real data about the behavior of your fans if you edit and run script ipmi/fan_measurement.sh
. The script will set fan levels from 100% to 20% in 5% steps and results will be saved in the file fan_result.csv
:
root:~# cat fan_result.csv
Level,FAN1,FAN2,FAN4,FANA,FANB
100,1300,1300,1200,1300,1300
95,1300,1300,1100,1200,1300
90,1200,1200,1100,1200,1200
85,1100,1100,1000,1100,1100
80,1100,1100,1000,1100,1100
75,1000,1000,900,1000,1000
70,900,900,800,1000,900
65,900,900,800,900,900
60,800,800,700,900,800
55,700,700,700,800,700
50,700,700,600,700,700
45,600,600,500,700,600
40,500,500,500,600,500
35,500,500,400,500,500
30,400,400,300,400,400
25,300,300,300,400,300
20,1300,1300,1200,1300,1300
My experience is that Noctua fans in my box are running stable in the 35-100% fan level interval. An additional user experience is (see issue #12) when Noctua fans are paired with Ultra Low Noise Adapter the minimum stable fan level could go up to 45% (i.e. 35% is not stable).
[CPU zone] / [HD zone] hwmon_path=
: This parameter is optional for Intel(R) CPUs and SATA drives (i.e. smfc
can identify automatically the proper file locations), but must be specified manually for AMD(R) CPUs. In case of SAS/SCSI hard disks (where drivetemp
cannot be loaded) you can specify hddtemp
value. You can use wild characters (?,*
) in this parameter and smfc
will do the path resolution automatically.
Several sample configuration files are provided for different scenarios in folder ./src/samples
. Please take a look on them, it could be a good starting point in the creation of your own configuration.
This systemd
service can be started and stopped in the standard way. Do not forget to reload systemd
configuration after a new installation or if you changed the service definition file:
systemctl daemon-reload
systemctl start smfc.service
systemctl stop smfc.service
systemctl restart smfc.service
systemctl status smfc.service
● smfc.service - Super Micro Fan Control
Loaded: loaded (/etc/systemd/system/smfc.service; enabled; vendor preset: enabled)
Active: active (running) since Fri 2021-09-17 23:28:10 CEST; 1 day 19h ago
Main PID: 1064180 (smfc.py)
Tasks: 1 (limit: 38371)
Memory: 7.4M
CPU: 41.917s
CGroup: /system.slice/smfc.service
└─1064180 /usr/bin/python3 /opt/smfc/smfc.py -c /opt/smfc/smfc.conf -l 2
Sep 19 17:12:39 home smfc.service[1064180]: CPU zone: new level > 39.0C > [T:40.0C/L:61%]
Sep 19 17:12:42 home smfc.service[1064180]: CPU zone: new level > 33.0C > [T:35.0C/L:48%]
Sep 19 17:48:14 home smfc.service[1064180]: CPU zone: new level > 38.0C > [T:40.0C/L:61%]
If you are testing your configuration, you can start smfc.py
directly in a terminal. Logging to the standard output and debug log level are useful in this case:
cd /opt
sudo smfc.py -o 0 -l 3
All messages will be logged to the specific output and the specific level.
With the help of command journalctl
you can check logs easily. For examples:
listing service logs of the last two hours:
journalctl -u smfc --since "2 hours ago"
listing service logs from the last boot:
journalctl -b -u smfc
Most probably the rotational speed of the fans went above or below of a threshold value You can check the current fan rotational speeds:
ipmitool sdr
and you can also check event log on Super Micro remote web interface (Server Health > Health Event log). If you see Assertions log messages for fans:
Fan(FAN1) Lower Critical - going low - Assertion
Fan(FAN1) Lower Non-recoverable - going low - Assertion
Fan(FAN1) Lower Non-recoverable - going low - Deassertion
Fan(FAN1) Lower Critical - going low - Deassertion
Fan(FAN4) Lower Critical - going low - Assertion
Fan(FAN4) Lower Non-recoverable - going low - Assertion
then you must adjust your configuration (i.e. threshold values) because IPMI switched back to full rotational speed.
You should configure the temperatures and levels with the same value.
min_temp=40
max_temp=40
min_level=60
max_level=60
With this setup there will be a constant 60% fan level in the specific zone. The temperature value is ignored, steps
parameter is also ignored.
The problem is that the specific file cannot be found in HWMON system. The potential reasons behind this issue could be:
drivetemp
driver cannot support your disks (it support only SATA hard disks). In case of SAS/SCSI hard disks you can use hddtemp
instead of drivetemp
. See more details in issue #21.hwmon_path=
parameter manually and it contains an invalid path. You can correct it.The configuration is the following:
64 GB ECC DDR4 RAM
Fractal Design Node 804 case, with separate chambers for the motherboard and the hard disks:
Debian Linux LTS (actually bookworm with backported Linux kernel 6.5)
8 x WD Red 12TB (WD120EFAX) hard disks in ZFS RAID
3 x Noctua NF-12 PWM fans (FAN1, FAN2, FAN4) in CPU zone
2 x Noctua NF-12 PWM fans (FANA, FANB) in HD zone
Further readings:
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