NUT Client - Proxmox Host

Proxmox host setup

Table of contents

1. Summary table of NUT Client - Proxmox Host files
2. Client Monitoring Configuration Files
   1. upsmon.conf
   2. nut.conf
3. Event Scheduling and Custom Actions
   1. upssched.conf
   2. upssched-cmd (User Script)

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Summary table of NUT Client - Proxmox Host files

These files are for my NUT clients that are running Proxmox PVE systems (pve10 and pve20).

The Synology NAS client is set up with different code.

Don’t edit your VM with this code!

All of these files are at the BARE METAL level on the Proxmox host.

This is a reminder because I keep looking for the NUT files in my VMs…😏

All my files are in etc/nut.

File	Purpose	File Directory	On Server?	On Client?
upsmon.conf	Configures UPS monitoring and shutdown logic	/etc/nut/upsmon.conf	✅	✅
nut.conf	Declares system role (netclient)	/etc/nut/nut.conf	✅	✅
upssched.conf	Configures timed/custom actions during UPS events	/etc/nut/upssched.conf	✅	✅
upssched-cmd	User-defined script triggered by upssched	/usr/nut/upssched-cmd)	✅	✅

Client Monitoring Configuration Files

upsmon.conf

• Purpose: Monitors UPS status and triggers system shutdown.
• Used by: upsmon
• Location: /etc/nut/upsmon.conf
• My file (client - Proxmox):

    RUN_AS_USER root
  
    MONITOR ups@192.168.0.10 1 upsmon secret slave
  
    MINSUPPLIES 1
    SHUTDOWNCMD "/sbin/shutdown -h"
    NOTIFYCMD /usr/sbin/upssched
    POLLFREQ 2
    POLLFREQALERT 1
    HOSTSYNC 15
    DEADTIME 15
    POWERDOWNFLAG /etc/killpower
  
    NOTIFYMSG ONLINE    "UPS %s on line power"
    NOTIFYMSG ONBATT    "UPS %s on battery"
    NOTIFYMSG LOWBATT   "UPS %s battery is low"
    NOTIFYMSG FSD       "UPS %s: forced shutdown in progress"
    NOTIFYMSG COMMOK    "Communications with UPS %s established"
    NOTIFYMSG COMMBAD   "Communications with UPS %s lost"
    NOTIFYMSG SHUTDOWN  "Auto logout and shutdown proceeding"
    NOTIFYMSG REPLBATT  "UPS %s battery needs to be replaced"
    NOTIFYMSG NOCOMM    "UPS %s is unavailable"
    NOTIFYMSG NOPARENT  "upsmon parent process died - shutdown impossible"
  
    NOTIFYFLAG ONLINE   SYSLOG+WALL+EXEC
    NOTIFYFLAG ONBATT   SYSLOG+WALL+EXEC
    NOTIFYFLAG LOWBATT  SYSLOG+WALL+EXEC
    NOTIFYFLAG FSD      SYSLOG+WALL+EXEC
    NOTIFYFLAG COMMOK   SYSLOG+WALL+EXEC
    NOTIFYFLAG COMMBAD  SYSLOG+WALL+EXEC
    NOTIFYFLAG SHUTDOWN SYSLOG+WALL+EXEC
    NOTIFYFLAG REPLBATT SYSLOG+WALL+EXEC
    NOTIFYFLAG NOCOMM   SYSLOG+WALL+EXEC
    NOTIFYFLAG NOPARENT SYSLOG+WALL
  
    RBWARNTIME 43200
  
    NOCOMMWARNTIME 600
  
    FINALDELAY 5
  

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nut.conf

• Purpose: Defines the system role: standalone, netserver, or netclient.
• Used by: All NUT services
• Location: /etc/nut/nut.conf
• My file:

  MODE=netclient   # on client
  

Event Scheduling and Custom Actions

upssched.conf

• Purpose: Provides hooks for custom actions or scripts during UPS events (like power failure or low battery).
• Used by: upsmon via upssched
• Location: /etc/nut/upssched.conf
• My file:

  # This script gets called to invoke commands for timers that trigger.
    CMDSCRIPT /etc/nut/upssched-cmd
  
    # Command pipe and lock-file
    PIPEFN /etc/nut/upssched.pipe
    LOCKFN /etc/nut/upssched.lock
  
    # Send alerts immediately on change in line power
    AT ONBATT * EXECUTE onbatt
    AT ONLINE * EXECUTE onpower
  
    # (Optional) Silence the beeper after 2 minutes
    # AT ONBATT * START-TIMER mute_beeper 120
    # AT ONLINE * CANCEL-TIMER mute_beeper
  
    # Shutdown after 10 minutes on battery (10 * 60 = 1200)
    AT ONBATT * START-TIMER onbatt_shutdown 600
  
    # Cancel timer if power is restored
    AT ONLINE * CANCEL-TIMER onbatt_shutdown
  
    # Battery replacement indicated by cron'd quick test
    AT REPLBATT * EXECUTE replace_batt
  
    AT LOWBATT * EXECUTE onbatt
    AT COMMBAD * START-TIMER commbad 30
    AT COMMOK * CANCEL-TIMER commbad commok
    AT NOCOMM * EXECUTE commbad
    AT SHUTDOWN * EXECUTE powerdown
  

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upssched-cmd (User Script)

• Purpose: A user-defined script that gets triggered by upssched to handle UPS events.
• Used by: upssched
• Location: User-defined (e.g., /usr/nut/upssched-cmd)
• My file:

    #! /bin/sh
    #
    # This script should be called by upssched via the CMDSCRIPT directive
    # in the first line of /etc/nut/upssched.conf
    #
  
    # START: User-specific settings                            
    #
    UPS_USERNAME="upsmon"
    UPS_PASSWORD="secret"
    UPS_LINK="ups@192.168.0.10"
    # END  
  
    case $1 in
        onbatt)
            # make sure beeper is enabled
            upscmd -u ${UPS_USERNAME} -p ${UPS_PASSWORD} ${UPS_LINK} beeper.enable
            # alert
            message="Power outage, on battery"
            logger -t upssched-cmd "$message"
            ;;
        onpower)
            message="Power restored"
            logger -t upssched-cmd "$message"
            ;;
        mute_beeper)
             message="(2) minute limit exceeded, muting beeper"
             upscmd -u ${UPS_USERNAME} -p ${UPS_PASSWORD} ${UPS_LINK} beeper.mute
             ;;
        onbatt_shutdown)
            message="Triggering shutdown after (10) minutes on battery"
            logger -t upssched-cmd "$message"
            /sbin/upsmon -c fsd
            ;;
        replace_batt)
            message="Quick self-test indicates battery requires replacement"
            logger -t upssched-cmd "$message"
            ;;
        *)
            logger -t upssched-cmd "Unrecognized command: $1"
            ;;
    esac
  

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