---
created: '"2024-04-08T22:34:39.830Z"'
type: '"note"'
updated: 2024-12-03T20:26:52.557Z
---

# crontab

```bash
crontab -l
crontab -r
crontab -e
```

```conf
*/2 * * * * nmap -n -sn -Pn 192.168.31.19 192.168.31.82 -oN /var/www/html/on-results.txt
```

- [calculator](https://crontab.guru/)

```conf 1733257409966 = 638688542099660000 = Tue Dec 03 2024 13:23:29 GMT-0700 (Mountain Standard Time)
# Edit this file to introduce tasks to be run by cron.
#
*/5 * * * * /etc/duckdns/duck.sh >/dev/null 2>&1
24 5 * * * "/root/.acme.sh"/acme.sh --cron --home "/root/.acme.sh" > /dev/null
24 13 * * * cd /root/jackyzha0-quartz-phares && /snap/bin/npx quartz build
```