#crontab — Public Fediverse posts

Backup your Crontab …

Yesterday evening I just quickly wanted to change something in my crontab .. I was tired, I was distracted, I just SSH’ed into my machine and typed crontab -r.

Ahh typo! I obviously wanted to crontab -e which is just ONE key away from -r. But … no error, no “unknown option”? This left me in a “eh what is -r and why is crontab -l empty?” – and I sensed a little disaster …

A quick check […]

Backup your Crontab …

Yesterday evening I just quickly wanted to change something in my crontab .. I was tired, I was distracted, I just SSH’ed into my machine and typed crontab -r.

Ahh typo! I obviously wanted to crontab -e which is just ONE key away from -r. But … no error, no “unknown option”? This left me in a “eh what is -r and why is crontab -l empty?” – and I sensed a little disaster …

A quick check […]

Edit/update: Keyboard Maestro has a cron and a periodic trigger, which will probably be the easiest/quickest solution for what I'm looking for right now. Thanks for reminding me, @Tom !

Earlier post:
If you were using crontab / cron and upgraded to macOS Tahoe 26.6, what workaround did you do to unbork cron?

Or, how are you scheduling your shell scripts to run at small intervals (on macOS Tahoe 26.6)?

#macOS #Tahoe #crontab #shell #scripts

Edit/update: Keyboard Maestro has a cron and a periodic trigger, which will probably be the easiest/quickest solution for what I'm looking for right now. Thanks for reminding me, @Tom !

Earlier post:
If you were using crontab / cron and upgraded to macOS Tahoe 26.6, what workaround did you do to unbork cron?

Or, how are you scheduling your shell scripts to run at small intervals (on macOS Tahoe 26.6)?

#macOS #Tahoe #crontab #shell #scripts

Почему cron — самый опасный инструмент в Linux

Демон cron знаком каждому, кто админит Linux. Он крутит бэкапы, чистит временные файлы и запускает скрипты, о которых все уже давно забыли. Однако многие не знают, что одна строка в crontab способна снести данные, забить диск, устроить форк-бомбу или открыть лазейку для хакера. Под катом я разберу, когда и как именно cron становится опасным, и какие команды помогут держать его в узде. Читать

https://habr.com/ru/companies/ruvds/articles/1052508/

#cron #linux #crontab #bash #shell #systemd #резервное_копирование #автоматизация #cronie #ruvds_статьи

"The dog ate my crontab!"

#dogs #crontab

Maintenance Proxmox & Docker : comment je suis devenu spectateur de mon infrastructure

https://blablalinux.be/2026/04/08/strategie-automatisation-globale/

Always the same in #SelfHosting ...

People: I forget to renew the (Let´s Encrypt) certificates ... mimimi
Me: my best buddy #crontab does that for me ​:floof_peek:​

Always the same in #SelfHosting ...

People: I forget to renew the (Let´s Encrypt) certificates ... mimimi
Me: my best buddy #crontab does that for me ​:floof_peek:​

Почему я написал Ёбифай: свой планировщик для фоновых задач на Python

Но очень быстро оказывается, что настоящая сложность не в самих задачах, а в инфраструктуре вокруг них. Сначала хочется просто запускать код в фоне. Потом появляются ретраи, таймауты, логирование, контроль выполнения. Ещё чуть позже всплывают совсем неприятные вопросы: что делать с пропущенными запусками после рестарта, как не дублировать задачи и где вообще должна жить логика планирования. В какой-то момент становится очевидно:

https://habr.com/ru/articles/1018646/

#scheduler #cron #crontab #cronjob #background_job #background_jobs #asyncio

Как мы устали настраивать Crontab и сделали свой cron-manager

В какой-то момент cron-заданий становится много, появляются сложные зависимости между скриптами, когда результат выполнение одного важен для начала работы другого. Балансировать такую историю доводится сис.админу, DevOps'у или разработчику. С этого и начинается наш рассказ.

https://habr.com/ru/articles/1003006/

#cron #crontab #cronjob #cronjob #продукт #продуктовая_разработка

Selfhosting is nice, and it comes with a price to pay.

For me ? It's time, and I have plenty to give away, given that's my passion.

For my SO ? The unbearable noise of rattling disk needles to write on their very precious platters (especially now, thank you AI bullcrap)

The solution ? A nice cron-based compromise, and I feel like someone could get inspired by this :)

# Stop qbittorrent - weekday evenings at 17:00 Mon-Fri
0 17 * * 1-5 cd /opt/services/qbittorrent && docker compose stop

# Stop qbittorrent - weekends at 8:00 Sat-Sun
0 8 * * 6,0 cd /opt/services/qbittorrent && docker compose stop

# Start qbittorrent - every day at 23:00
0 23 * * * cd /opt/services/qbittorrent && docker compose start

#selfhosting #selfhosted #homelab #torrent #qbittorrent #harddrive #disk #nas #so #ai #cron #crontab #scheduling #linux #opensource #docker #dockercompose

Selfhosting is nice, and it comes with a price to pay.

For me ? It's time, and I have plenty to give away, given that's my passion.

For my SO ? The unbearable noise of rattling disk needles to write on their very precious platters (especially now, thank you AI bullcrap)

The solution ? A nice cron-based compromise, and I feel like someone could get inspired by this :)

# Stop qbittorrent - weekday evenings at 17:00 Mon-Fri
0 17 * * 1-5 cd /opt/services/qbittorrent && docker compose stop

# Stop qbittorrent - weekends at 8:00 Sat-Sun
0 8 * * 6,0 cd /opt/services/qbittorrent && docker compose stop

# Start qbittorrent - every day at 23:00
0 23 * * * cd /opt/services/qbittorrent && docker compose start

#selfhosting #selfhosted #homelab #torrent #qbittorrent #harddrive #disk #nas #so #ai #cron #crontab #scheduling #linux #opensource #docker #dockercompose

I recently had to do a complete wipe and re-install of my #wpsd #hamradio #hotspot.
Most of the settings were retained by wpsd's backup/restore functions, but my #crontab had to be recreated from scratch.

Luckily I had blogged some of it last year:
https://blog.k3can.us/posts/2025/mar/2025-03-13_automatinganam/
#amateurradio

Show me your #crontab

Show me your #crontab

Yeah meine zweite Festplatte ist heute angekommen !

/dev/sdb 983379700 400782140 5325 43% /mnt/data

/dev/sdc1 983378676 307661060 6256 33% /mnt/data2

Jetzt nur noch mit einem #rsync job täglich #crontab alles von einer Platte auf die andere Platte schaufeln und ich habe wenigstens schonmal ein bisschen #Ausfallsicherheit #backup #Datensicherung für meinen #HomeServer realisiert.

Parallel mache mit "duplicati" ein verschlüsseltes Backup des Betriebssystems in mein #ondrive da habe ich noch 1 TB, warum nicht nutzen wenn man es eh schon hat.

@gary_alderson Indeed. Remember to enable the actualize script through #crontab: https://freshrss.github.io/FreshRSS/en/admins/08_FeedUpdates.html

🔍 / #software / #library / #python

#Crontab module for reading and writing crontab files and accessing the system #cron automatically and simply using a direct API.

🐱🔗 https://laravista.altervista.org/CatLink/links/325

#catlink #SoftwareLibrary #SoftwareLibraryPython #PythonCrontab

JSON just popped into my head:

https://ecma-international.org/wp-content/uploads/ECMA-404_2nd_edition_december_2017.pdf

This PDF, and the website (https://www.json.org/json-en.html) have syntax diagrams for each bit, but I don't see any formal grammar definition being used, which is surprising.

I've not checked what YAML does, but it's just interesting to note.

Heck, even #crontab's config file has BNF in the man page... or used to, I've checked lately.

JSON just popped into my head:

https://ecma-international.org/wp-content/uploads/ECMA-404_2nd_edition_december_2017.pdf

This PDF, and the website (https://www.json.org/json-en.html) have syntax diagrams for each bit, but I don't see any formal grammar definition being used, which is surprising.

I've not checked what YAML does, but it's just interesting to note.

Heck, even #crontab's config file has BNF in the man page... or used to, I've checked lately.

【bash】ディスク容量をチェックして閾値を超えたらアラートメールを送信
https://qiita.com/kojimura/items/67f6bd8e9b959cdffc49?utm_campaign=popular_items&utm_medium=feed&utm_source=popular_items

#qiita #Bash #Linux #サーバー管理 #自動化 #crontab

Зачем нужен ArgoCD, если можно поставить cron с git pull?

Инфраструктура как код, GitOps, автоматизация — все эти слова давно перестали быть модными терминами и стали частью повседневной жизни инженера. Но вместе с этим появляются и вопросы: а всегда ли нужно внедрять тяжелые инструменты? Например, зачем нужен ArgoCD, если можно просто настроить cron с git pull на нужный сервер? Попробуем разобраться, в чём разница между этими подходами, какие задачи они решают, где их границы применимости и, главное, в каких случаях cron — это «дешево и сердито», а когда он становится «дешево, но больно».

https://habr.com/ru/articles/912014/

#argocd #devops #gitops #cron #crontab #автоматизация #cd #continuous_deployment

Today I hate #InnoDB fragmentation, and incompatible #crontab files across different versions of #cron

Today I hate #InnoDB fragmentation, and incompatible #crontab files across different versions of #cron

I was configuring a daily crontab task and I couldn't resist:

20 16 * * *

xD

#crontab

#question #bash #crontab #mysql :

j'ai un script qui fait

for db in database1 database2 database3;
do
echo $db
if [[ "$db" != "database2" ]]; then
echo "dumping database $db"
mysqldump -u $USER -p$PASSWORD --databases $db > $db.sql
fi
done

quand je le lance directement, pas de souci, ça fonctionne. mais en tâche #cron, rien, que dalle, que pouic, mon cul dans les orties.
et je ne vois pas pourquoi.

Une idée ?

Edit : La solution à mon problème ici par @Dominix :

https://mastodon.social/@Dominix/114132696033730693

#question #bash #crontab #mysql :

j'ai un script qui fait

for db in database1 database2 database3;
do
echo $db
if [[ "$db" != "database2" ]]; then
echo "dumping database $db"
mysqldump -u $USER -p$PASSWORD --databases $db > $db.sql
fi
done

quand je le lance directement, pas de souci, ça fonctionne. mais en tâche #cron, rien, que dalle, que pouic, mon cul dans les orties.
et je ne vois pas pourquoi.

Une idée ?

Edit : La solution à mon problème ici par @Dominix :

https://mastodon.social/@Dominix/114132696033730693

🐧 Que ce soit en local ou sur votre serveur, Crontab permet de programmer des scripts et actions qui se feront à intervalle régulier sur votre machine. Très pratique, même pour des choses assez basique. Ça fait des années que j'utilise Linux au quotidien mais paradoxalement j'ai commencé à m'emparer de crontab réellement il y a assez peu de temps.
Bref comme les intervalles sont une galère à indiquer, ce site est bien pratique pour les encoder https://crontab.cronhub.io/

#linux #crontab

🐧 Que ce soit en local ou sur votre serveur, Crontab permet de programmer des scripts et actions qui se feront à intervalle régulier sur votre machine. Très pratique, même pour des choses assez basique. Ça fait des années que j'utilise Linux au quotidien mais paradoxalement j'ai commencé à m'emparer de crontab réellement il y a assez peu de temps.
Bref comme les intervalles sont une galère à indiquer, ce site est bien pratique pour les encoder https://crontab.cronhub.io/

#linux #crontab

Wieso hat die Welt eigentlich keine coole kleine #GUI für die #crontab erfunden?

So nach 40 Jahren wär's fei scho mol Zeit, gell?

(Oder wieso gibt es nix Gnome Scheduler mäßiges mehr?)

#cron #linux

Wieso hat die Welt eigentlich keine coole kleine #GUI für die #crontab erfunden?

So nach 40 Jahren wär's fei scho mol Zeit, gell?

(Oder wieso gibt es nix Gnome Scheduler mäßiges mehr?)

#cron #linux

@dside Чтобы не пропустить заранее известную дату (например, продлить домен или сертификат), прекрасно справится #crontab.

Y otra entrada en la #Wiki que me faltaba: https://docs.lynze.net/books/linux/page/cron
Apuntes sobre #cron
#Linux #crontab

#Linux
#Debian
#systemd
#crontab

#Linux
#Debian
#systemd
#crontab

OpenBSD crond / crontab set_range() heap underflow - CVE-2024-43688

https://www.supernetworks.org/CVE-2024-43688/openbsd-cron-heap-underflow.txt

https://vulnerability.circl.lu/cve/CVE-2024-43688

#vulnerability #cron #crontab #infosec #crond #openbsd #unix

Automating Tasks with Cron https://linuxexpert.org/automating-tasks-with-cron/

#crontab #linux

cronを業務で使用して学んだこと
https://qiita.com/Takashi5816/items/0812004ac5920027e16d?utm_campaign=popular_items&utm_medium=feed&utm_source=popular_items

#qiita #Linux #cron #crontab

Need a pet sitter for your aquarium while you’re away? Create an automatic feeder with a Raspberry Pi Zero. https://www.makerspace-online.com/fish-food/ #automation #feeder #RaspberryPi #ZeroW #network #CLI #CommandLine #crontab #projects #makers

Documentando el uso más común de las tareas programadas con #cron #crontab #wiki #linux @fedora

https://mainkivi.info/wiki/index.php?title=Cron

Yesterday, I wrote a small #bash script for sending me the status of our #SolarPower system as notifications on my #SmartWatch using ntfy.sh. Added an entry to #crontab to have script run automatically.

This is my first notification of the day.

How To Prevent Crontab Entries From Accidental Deletion In Linux #Crontab #Cron #Linux #Cronjob #Linuxhowto #Linuxtips #Linuxadmin
https://ostechnix.com/prevent-crontab-entries-from-accidental-deletion/

Når WP_CRON er slått av og disse kjører istedenfor vha. wp-cli i en crontab-jobb hvert 5 minutt så ser en at det er litt aktivitet fra f.eks. mastodon.social for kontoer som blir slettet.

Følgende:

wp cron event list \  --fields=hook,next_run_relative,argsCode language: Bash (bash)

gir da:

https://aslakr.folk.ntnu.no/2024/01/activitypub_delete_actor/

#ActivityPub #cron #crontab #WordPress #wpCli

Them: Rob, you know #Unix, right?

Me: I’ve been using Unix and Unix-like systems for three decades, from kernel internals to writing my own terminal emulator and X window manager on up. I think it’s safe to say that I “know Unix” my friend. 😏

Them: Okay great so can you help me write a #crontab entry?

Me: *screams internally*

I just changed my #crontab for #mastodon. It now runs the shell script at this URL as it describes. I think it's better than the default. For me, anyway.

https://ricard.dev/improving-mastodons-disk-usage/

I've just asked #Bard #AI to write a #poem about what I'm currently doing in work (editing a #crontab) and it's done a pretty good job. 😂

I'm editing my crontab,
I'm trying to get it right,
I want it to run every day,
At a specific time of night.

I've set the minute and hour,
And the day of the week,
I've even set the month and year,
I think it's all complete.

I save my changes and exit,
And cross my fingers and hope,
That my cron job will run as planned,
And not crash and burn my hopes.