nut-server with E-Mail alerts

🚀 Docker Modification Steps

1. Modify your docker compose. The red bolded lines are what's added.

services:
  nut-server:
    image: nut-server-smtp
    container_name: nut-server
    restart: unless-stopped
    privileged: true
    build: .
    environment:
      - TZ=America/New_York
      - UPS_NAME=apc600
      - UPS_DRIVER=usbhid-ups
      - UPS_PORT=auto
      - UPS_DESC=APC BE600M1
      - USERNAME=YOUR-USERNAME
      - PASSWORD=YOUR-PASSWORD
    entrypoint:
      - /bin/sh
      - -c
      - |
          mkdir -p /var/run/nut
          chown nut:nut /var/run/nut
          /usr/sbin/upssched &
          exec /usr/local/bin/entrypoint.sh
    devices:
      - /dev/bus/usb:/dev/bus/usb
    ports:
      - "3493:3493"
    volumes:
      - ./config:/etc/nut
      - ./logs:/var/log/nut
      - ./upssched-cmd.sh:/usr/local/bin/upssched-cmd.sh
      - ./send-email.sh:/usr/local/bin/send-email.sh
      - ./msmtprc:/etc/msmtprc:ro
      - ./msmtp.log:/var/log/msmtp.log

2. Create upssched-cmd.sh

   In ~/docker/nut, create upssched-cmd.sh:

   #!/bin/sh
   
   case "$1" in
     notify-on-battery)
       /usr/local/bin/send-email.sh "UPS on battery" "Your UPS has switched to battery power."
       ;;
     notify-on-line)
       /usr/local/bin/send-email.sh "UPS back on line" "Your UPS has returned to AC power."
       ;;
   esac

   Make it executable: chmod 666 upssched-cmd.sh

3. Create send-email.sh

In ~/docker/nut, create send-email.sh:

#!/bin/sh
SUBJECT="$1"
BODY="$2"

echo -e "Subject: $SUBJECT\n\n$BODY" | msmtp t;Your-Email-Address>

Make it executable: chmod 666 send-email.sh

4. Create Dockerfile

In ~/docker/nut, create Dockerfile:

FROM instantlinux/nut-upsd:latest
RUN apk add --no-cache msmtp

Build nut

From within ~/docker/nut run this: docker compose build

Start it

From within ~/docker/nut run this: docker compose up -d

Test it

Unplug the UPS from the wall. Wait a few seconds and plug it back in. You should get two emails, one telling you that you're on battery and one saying that you're back online.

📜 View Logs

You can also see the email log by looking in ~/docker/nut/msmtp.log