title: Linux hardware: fans
agents: linux
catalog: os/hardware
license: GPLv2
distribution: check_mk
description:
 Fan speed (rpm) of a Linux host from hwmon (notebook firmware such as dell_smm or
 thinkpad, mainboard chips, GPUs), the share of the fan's maximum and the speed the
 firmware is aiming at. A fan fault reported by the driver is CRIT, an alarm WARN.
 No speed levels by default (notebook fans stand still when idle); they can be set
 with the rule "Linux hardware: fan".

item:
 The fan's label, or "System" (single unlabeled notebook/mainboard fan), "System N"
 for several unlabeled mainboard headers, "GPU" for a graphics card.

discovery:
 One service per fan. Headers without a fan (0 rpm and no maximum) are skipped, as
 are fans of a driver that only repeats another driver's readings. Two fans with
 the same speed on different chips get a note in the output.
