unifi lb notification

https://community.ubnt.com/t5/EdgeMAX/WAN-Failure-notification/td-p/771248/page/2

I know I'm resurrecting an old thread, but here's the script and command I used.  Hopefully it helps someone.
 
It's pretty basic, but it works.  I used an external SMTP delivery service, Mailgun, to handle the email transport - this allows me to just use curl to send the message via their API.  Mailgun is free for upto 10,000 emails/month.
 
set load-balance group WAN_FAILOVER transition-script /config/scripts/wlb-notification
 
#!/bin/bash

# Echo usage if no arguments passed
if [ $# -eq 0 ]
then
  echo "Usage: $0 [group ] [interface] [status]"
        exit 0
fi

curl=/usr/bin/curl

group=$1
interface=$2
status=$3

curl -s --user 'api:xxxxxxxxxxxxxxxxxxxxxx' \
    https://api.mailgun.net/v2/xxxxxxxxxxxx.com/messages \
    -F from='xxxxxxxxxxx <xxxxxxxxxx@xxxxxxxx.com>' \
    -F to='xxxx xxxxxx <xxxxxxxxxx@xxxxxxxxx.com>'\
    -F subject="ALERT:  Internet Connection on $interface status $status" \
    -F text="ALERT:  Internet Connection on $interface status $status"