---
name: "sensorsd"
section: "8"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/sensorsd"
---

# sensorsd(8)

hardware sensors monitor

## NAME

**sensorsd** – hardware sensors monitor

## SYNOPSIS

**sensorsd** \[**-d**\] \[**-c** *check*\] \[**-f** *file*\]

## DESCRIPTION

The **sensorsd** utility retrieves sensor monitoring data like fan speed, temperature, voltage and RAID logical disk status from the [sysctl(2)](/sysctl/2.md) *hw.sensors* subtree. When the state of any monitored sensor changes, an alert is triggered. Every alert logs a message to [syslog(3)](/syslog/3.md) using the **daemon** facility. Optionally, an alert can be configured to execute a command.

By default, **sensorsd** monitors status changes on all sensors that keep their state, thus sensors that automatically provide status do not require any additional configuration. In addition, for every sensor, no matter whether it automatically provides its state or not, custom low and high limits may be set, so that a local notion of sensor status can be computed by **sensorsd**, indicating whether the sensor is within or is exceeding its limits.

Limit and command values for a particular sensor may be specified in the [sensorsd.conf(5)](/sensorsd.conf/5.md) configuration file. This file is reloaded upon receiving SIGHUP.

The options are as follows:

- **-c** *check*

  Check sensors every *check* seconds. The default is 20. The state of a sensor is not yet regarded as changed when a check returns a new state for the first time, but only when the two subsequent checks both confirm the new state.

- **-d**

  Do not daemonize. If this option is specified, **sensorsd** will run in the foreground.

- **-f** *file*

  Read configuration from *file* instead of the default configuration file */etc/sensorsd.conf*.

## FILES

- */etc/sensorsd.conf*

  Configuration file for **sensorsd**.

## SEE ALSO

[sysctl(2)](/sysctl/2.md), [sensorsd.conf(5)](/sensorsd.conf/5.md), [syslog.conf(5)](/syslog.conf/5.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

The **sensorsd** program first appeared in OpenBSD 3.5.

## CAVEATS

Certain sensors may erratically flip status from time to time. To guard against false reports, **sensorsd** requires two confirmations before reporting a state change. However, this inevitably introduces an additional delay in status reporting and command execution, e.g. one may notice that **sensorsd** makes its initial report about the state of monitored sensors not immediately, but by default about 60 seconds after it is started.