twn:~$ cat /etc/cron.hourly/systemd-failed-service-notify 
#!/bin/bash

mapfile -t services < <(
    systemctl list-units --state=failed --type=service --plain --no-legend --no-pager |
    awk '{ print $1 }'
)

count=${#services[@]}

if [ "$count" -gt 0 ]; then
    /home/betawiki/config/bin/udpcast \
        "WARNING: $count failed systemd service(s): ${services[*]}"
fi