# NUT.CONF(5)

## NAME

nut.conf - UPS definitions for Network UPS Tools

## DESCRIPTION

This file attempts to standardize the various files being found in different installations, like `/etc/default/nut` on Debian based systems and `/etc/sysconfig/ups` on RedHat based systems.

Distribution’s init script should source this file in order to determine which components have to be started.

Blank lines are ignored. Lines with a hash (`#`) character at the first position of the line are ignored, too. They can be used to add comments.

## IMPORTANT NOTES

- This file is intended to be sourced by shell scripts as well as by service management frameworks like systemd on Linux:

  - There is no guaranteed `export VAR=VAL` syntax

  - No guaranteed expansion of variables like `VAR1="$VAR2-something"`—  only verbatim assignments

  - You may need to `export VAR` when sourcing it into init-scripts or other scripts, for eventual propagation of certain settings to NUT programs. Not-exported variables can only be consumed by the script which "sourced" the file (and may choose to `export` them independently).

- You MUST NOT use spaces around the equal sign!

- Practical support for this file and its settings currently varies between different OS packages and NUT sample scripts, but should converge over time.

- Contents of this file should be pure ASCII (character codes not in range would be ignored with a warning message).

Refer to the EXAMPLE section for illustrations.

## DIRECTIVES

MODE

  Required. Recognized values are none, standalone, netserver and netclient. Defaults to none.

  none

    Indicates that NUT should not get started automatically, possibly because it is not configured or that an Integrated Power Management or some external system, is used to startup the NUT components.

  standalone

    Addresses a local only configuration, with 1 UPS protecting the local system. This implies to start the 3 NUT layers (driver, upsd and upsmon), with the related configuration files. This mode can also address UPS redundancy.

  netserver

    Like the standalone configuration, but also possibly need one or more specific LISTEN directive(s) in upsd.conf. Since this MODE is open to the network, a special care should be applied to security concerns.

  netclient

    When only upsmon is required, possibly because there are other hosts that are more closely attached to the UPS, the MODE should be set to netclient.

ALLOW_NO_DEVICE

  Optional, defaults to `false`. Set this to `true` to allow starting the `upsd` NUT data server service even if `ups.conf` has no device sections configured at the moment. This environment variable overrides the built-in "false" flag value in the `upsd` program, and an optional same-named default flag that can be set in `upsd.conf`.

  If you want a data server always running and responding on the network, even if it initially has nothing to serve (may be live-reloaded later, when devices become configured), this option is for you.

ALLOW_NOT_ALL_LISTENERS

  Optional, defaults to `false`. Set this to `true` to allow starting the `upsd` NUT data server even if not all `LISTEN` directives can be honoured at the moment. This environment variable overrides the built-in "false" flag in the `upsd` program, and an optional same-named default flag that can be set in `upsd.conf`.

  If you want a data server always running, even if it would potentially not serve all clients on every uptime, this option is for you (note you would have to restart `upsd` to pick up the `LISTEN`ed IP address if it appears later).

  Probably configuring `LISTEN *` is a better choice in such cases.

UPSD_OPTIONS

  Optional. Set upsd specific options. See upsd(8) for more details. It is ignored when MODE above indicates that no upsd should be running.

UPSMON_OPTIONS

  Optional. Set upsmon specific options. See upsmon(8) for more details. It is ignored when MODE above indicates that no `upsmon` should be running.

POWEROFF_WAIT

  Optional. At the end of an emergency system halt, the upsmon primary will signal the UPS to switch off. This may fail for a number of reasons. Most notably is the case that mains power returns during the shutdown process. See the section "Power races" in `/usr/share/doc/nut/FAQ.txt.gz`. The system will wait this long for the UPS to cut power, and then reboot. It should be long enough to exhaust the batteries, in case line power continues to be unavailable. On the other hand, it should not be so long that the system remains offline for an unreasonable amount of time if line power has returned. See sleep(1) for compatible time syntax. If you specify the time in seconds, use the "s" suffix.

  Warning | This workaround might be dangerous under some circumstances. Please read http://bugs.debian.org/358696 for more details.

POWEROFF_QUIET

  Optional, defaults to `false`. This setting controls if the NUT shutdown integration scripts or service units would emit messages about their activity (or lack thereof). By default they may be verbose, to aid in post-mortem troubleshooting via logs or console captures. Set to `true` to avoid that trove of information, if you consider it noise.

NUT_DEBUG_LEVEL

  Optional, defaults to `0`. This setting controls the default debugging message verbosity passed to NUT daemons. As an environment variable, its priority sits between that of DEBUG_MIN setting of a driver and the command-line options.

NUT_DEBUG_PID

  Optionally add current process ID to tags with debug-level identifiers. This may be useful when many NUT daemons write to the same console or log file, such as in containers/plugins for Home Assistant, storage appliances…

NUT_DEBUG_SYSLOG

  Optional, unset by default. Normally NUT can (attempt to) use the syslog or Event Log (WIN32), but the environment variable NUT_DEBUG_SYSLOG allows to bypass it, and perhaps keep the daemons logging to stderr (useful e.g. in NUT Integration Test suite to not pollute the OS logs, or in systemd where stderr and syslog both go into the same journal). Recognized values:

  Value | Description
  --- | ---
  `stderr` |
      Disabled and `background()` keeps `stderr` attached
  `none` |
      Disabled and `background()` detaches `stderr` as usual
  `default` |
      Not disabled
  unset/other |
      Not disabled

NUT_IGNORE_CHECKPROCNAME

  Optional, defaults to `false`. Normally NUT can (attempt to) verify that the program file name matches the name associated with a running process, when using PID files to send signals.

  The `NUT_IGNORE_CHECKPROCNAME` boolean toggle allows to quickly skip such verification, in case it causes problems (e.g. NUT programs were renamed and do not match built-in expectations).

  This environment variable can also be optionally set in init-scripts or service methods for `upsd`, `upsmon` and NUT drivers/`upsdrvctl`.

NUT_QUIET_INIT_UPSNOTIFY

  Optional flag to prevent daemons which can notify service management frameworks (such as systemd) about passing their lifecycle milestones, to not report loudly if they could NOT do so (e.g. running on a system without a framework, or misconfigured so they could not report and the OS could eventually restart the false-positively identified "unresponsive" service.

  Currently such reports, done by default, help troubleshoot service start-up and highlight that NUT sources (or package build) did not take advantage of tighter OS service management framework integration (if one exists, so that developers could focus on adding that). Reasons to set this flag could include platforms without such a framework and not expecting one, although nagging your favourite OS or contributing development to make it better is also a way.

## EXAMPLE

       # /etc/nut/nut.conf.  See nut.conf(5)

       MODE=none

       UPSD_OPTIONS=""

       UPSMON_OPTIONS=""

       # POWEROFF_WAIT=15m

## INTEGRATION

An init script, such as `/etc/init.d/nut`, is expected to source this file in order to determine which components have to be started.

## SEE ALSO

ups.conf(5), upsd.conf(5), upsd.users(5), upsmon.conf(5)

### Internet resources:

The NUT (Network UPS Tools) home page: https://www.networkupstools.org/historic/v2.8.4/