One-shot job with at cron
Schedule a single deferred command; inspect queue with atq, cancel with atrm
at now + 1 hour <<< 'systemctl restart nginx'
more cron
all 8 commands →
Defer until load is low
batch <<< '/opt/heavy-reindex.sh'
Dump another user's crontab
crontab -l -u <name> 2>/dev/null || echo 'no crontab'
Run job at boot
( crontab -l 2>/dev/null; echo '@reboot /usr/local/bin/warmup.sh' ) | crontab -
Pipe cron output to syslog
*/5 * * * * /opt/job.sh 2>&1 | /usr/bin/logger -t job
MAILTO and PATH header
crontab - <<'EOF'
MAILTO=ops@example.com
PATH=/usr/local/bin:/usr/bin:/bin
0 3 * * * backup.sh
EOF