---
name: "lom"
section: "4"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/lom"
---

# lom(4)

lights out management

## NAME

**lom** – lights out management

## SYNOPSIS

**lom\* at ebus?**

## DESCRIPTION

The **lom** driver provides support for the LOMlite lights out management module found on Sun Netra t1 systems and the LOMlite2 module found on Sun Fire V100/V120 and Sun Netra X1 systems. Temperature readings, PSU status and fan status provided by the LOM are made available through the [sysctl(8)](/sysctl/8.md) interface. The integrated [watchdog(4)](/watchdog/4.md) timer can be configured through the [sysctl(8)](/sysctl/8.md) interface as well. The watchdog timer supports timeouts between 1 and 126 seconds. If the watchdog is disabled, which is its default state, it will turn on the system's fault LED after the maximum timeout of 126 seconds.

The **lom** driver will update the hostname stored in the LOM whenever the system's hostname is changed.

## SEE ALSO

[hostname(1)](/hostname/1.md), [ebus(4)](/ebus/4.md), [intro(4)](/intro/4.md), [watchdog(4)](/watchdog/4.md), [sensorsd(8)](/sensorsd/8.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

The **lom** driver first appeared in OpenBSD 4.7.

## AUTHORS

The **lom** driver was written by Mark Kettenis ⟨*kettenis@openbsd.org*⟩.