How to Set Up apcupsd for Eaton UPS on Debian Linux

Last updated: Feb 25, 2025

In this article, we'll look at how to configure the apcupsd service on Debian to manage a UPS connected via USB cable.

With apcupsd, you can:
- Automatically shut down the server when the UPS battery is low
- Log power failure
- Execute a script in the event of a power failure

Install and Configure

Install the apcupsd package:

root@debian:~# apt update && apt install apcupsd

Check that the UPS is visible:

root@debian:~# lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 1604:10c0 Tascam Dell Integrated Hub
Bus 001 Device 004: ID 1604:10c0 Tascam Dell Integrated Hub
Bus 001 Device 003: ID 1604:10c0 Tascam Dell Integrated Hub
Bus 001 Device 002: ID 0463:ffff MGE UPS Systems UPS
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Configuration

Edit the configuration file /etc/apcupsd/apcupsd.conf:

UPSCABLE usb
UPSTYPE usb
#remove /dev/ttyS0 when connected via USB :
#DEVICE /dev/ttyS0
DEVICE
LOCKFILE /var/lock
SCRIPTDIR /etc/apcupsd
PWRFAILDIR /etc/apcupsd
NOLOGINDIR /etc
ONBATTERYDELAY 6
BATTERYLEVEL 5
MINUTES 3
TIMEOUT 0
ANNOY 300
ANNOYDELAY 60
NOLOGON disable
KILLDELAY 0
NETSERVER on
NISIP 127.0.0.1
NISPORT 3551
EVENTSFILE /var/log/apcupsd.events
EVENTSFILEMAX 10
UPSCLASS standalone
UPSMODE disable
STATTIME 0
STATFILE /var/log/apcupsd.status
LOGSTATS off
DATATIME 0

Restart the apcupsd service:

root@debian:~# systemctl restart apcupsd.service

Run the apcaccess command to retrieve UPS status information:

root@debian:~# apcaccess status

APC      : 001,029,0694
DATE     : 2023-03-19 15:59:08 +0100
HOSTNAME : debian
VERSION  : 3.14.14 (31 May 2016) debian
UPSNAME  : std
CABLE    : USB Cable
DRIVER   : USB UPS Driver
UPSMODE  : Stand Alone
STARTTIME: 2023-02-27 16:36:50 +0100
MODEL    : Eaton 5P
STATUS   : ONLINE
LOADPCT  : 15.0 Percent
BCHARGE  : 100.0 Percent
TIMELEFT : 49.9 Minutes
MBATTCHG : 5 Percent
MINTIMEL : 3 Minutes
MAXTIME  : 0 Seconds
OUTPUTV  : 236.2 Volts
DWAKE    : -1 Seconds
ALARMDEL : 30 Seconds
LINEFREQ : 49.9 Hz
NUMXFERS : 0
TONBATT  : 0 Seconds
CUMONBATT: 0 Seconds
XOFFBATT : N/A
SELFTEST : OK
STATFLAG : 0x05000008
SERIALNO : G117N70614
NOMPOWER : 1100 Watts
END APC  : 2023-03-19 15:59:51 +0100

Logs

View apcusd logs with the journalctl command:

root@debian:~# journalctl -u apcupsd --since "120 min ago"
oct. 10 13:13:07 debian-server systemd[1]: Starting apcupsd.service - UPS power management daemon...
oct. 10 13:13:07 debian-server systemd[1]: apcupsd.service: Can't open PID file /run/apcupsd.pid (yet?) after start: No such file or directory
oct. 10 13:13:07 debian-server apcupsd[1714]: apcupsd 3.14.14 (31 May 2016) debian startup succeeded
oct. 10 13:13:07 debian-server apcupsd[1714]: NIS server startup succeeded
oct. 10 13:13:07 debian-server systemd[1]: Started apcupsd.service - UPS power management daemon.