Cron — алерт когда задача не запустилась по расписанию

#!/usr/bin/env bash
# /etc/cron.d/cron-skipped
# Run this at the END of the cron job you want to monitor:
#   30 3 * * * root /opt/some-job.sh && /opt/cron-ping.sh some-job
# /opt/cron-ping.sh — sends success ping with name

NAME=${1:?usage: cron-ping.sh <job-name>}
curl -fsS "$HEARTBEAT_URL/cron/$NAME" --data "ts=$(date +%s)"

# A separate guard runs at 03:45 (15 min AFTER the expected window)
# and complains if no ping arrived. That's a "dead-man's switch" —
# if the monitor itself has retention you need NOTHING ELSE on the box:
#   45 3 * * * root /opt/cron-watchdog.sh some-job