|FANCONTROL(8)||System Manager's Manual||FANCONTROL(8)|
In practice it doesn't seem to be a major issue, the fans will get slightly warmer, just be sure to have a temperature alarm and/or shutdown call, in case some fan fails, because you probably won't hear it anymore ;)
Since most of you are going to use pwmconfig(8) script, the config file syntax will be discussed last. First I'm going to describe the various variables available for changing fancontrol's behaviour:
- This variable defines at which interval in seconds the main loop of fancontrol will be executed
- Maps hwmon class devices to physical devices. This lets fancontrol check that the configuration file is still up-to-date.
- Records hwmon class device names. This lets fancontrol check that the configuration file is still up-to-date.
- Maps PWM outputs to temperature sensors so fancontrol knows which temperature sensors should be used for calculation of new values for the corresponding PWM outputs.
- Records the association between a PWM output and a fan input. Then fancontrol can check the fan speed and restart it if it stops unexpectedly.
- The temperature below which the fan gets switched to minimum speed.
- The temperature over which the fan gets switched to maximum speed.
- Sets the minimum speed at which the fan begins spinning. You should use a safe value to be sure it works, even when the fan gets old.
- The minimum speed at which the fan still spins. Use a safe value here, too.
- The PWM value to use when the temperature is below MINTEMP. Typically, this will be either 0 if it is OK for the fan to plain stop, or the same value as MINSTOP if you don't want the fan to ever stop. If this value isn't defined, it defaults to 0 (stopped fan).
- The PWM value to use when the temperature is over MAXTEMP. If this value isn't defined, it defaults to 255 (full speed).
- How many last temperature readings are used to average the temperature. It can be used to smoothen short temperature peaks. If this value isn't defined, it defaults to 1 (no averaging).
The configuration file format is a bit strange:
VARIABLE=chip/pwmdev=value chip/pwmdev2=value2 VARIABLE2=...
Each variable has its own line. The variable name is followed by an equal sign and the device=value pairs. These consist of the path to the pwm output for which the value is valid, equal sign followed by the value and are separated by a blank. Path can be absolute or relative (from /sys/bus/i2c/devices or /sys/class/hwmon depending on the kernel version). Example:
- MINTEMP=hwmon0/device/pwm1=40 hwmon0/device/pwm2=54
You have to play with the temperature values a bit to get happy. For initial setup I recommend using the pwmconfig script. Small changes can be made by editing the config file directly following the rules above.
Upon starting, fancontrol will make sure that all referenced devices do exist and match what they were at configuration time, and that all referenced sysfs files do exist. If not, it will quit immediately, upon the assumption that the configuration file may be out-of-sync with the loaded kernel drivers.
|September 2009||lm-sensors 3|