57 lines
2.1 KiB
Markdown
57 lines
2.1 KiB
Markdown
---
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layout: page
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title: "I used cron for the first time"
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description: "And I didn't die"
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date: 2019-12-11
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tags: random
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redirect_from:
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- /post/cd9dj84kf0/
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- /cd9dj84kf0/
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aliases: [/blog/2019/12/11/cron]
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---
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[Cron](https://en.wikipedia.org/wiki/Cron) has always been one of those "scary sysadmin things" in my head. But today, I finally used it!
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## My need
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I have access to a private API that happens to clear it's users if they are inactive for too long. To solve this, I decided to add a small cron job to make an API call once per month. Basically a [keepalive](https://en.wikipedia.org/wiki/Keepalive).
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## How I set it up
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Adding a cron job to my laptop was very easy. First, I made a bash script for my api call (not needed, but I felt like doing it).
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```sh
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#! /bin/bash
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curl --include --header "Accept: application/xml" '<API Endpoint Here>' --user $1:$2
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```
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Then, by running `crontab -e` in my terminal, I just added a new line at the bottom of the file, discribing the task, and when it should be run.
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```cron
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# Edit this file to introduce tasks to be run by cron.
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#
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# Each task to run has to be defined through a single line
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# indicating with different fields when the task will be run
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# and what command to run for the task
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#
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# To define the time you can provide concrete values for
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# minute (m), hour (h), day of month (dom), month (mon),
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# and day of week (dow) or use '*' in these fields (for 'any').#
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# Notice that tasks will be started based on the cron's system
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# daemon's notion of time and timezones.
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#
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# Output of the crontab jobs (including errors) is sent through
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# email to the user the crontab file belongs to (unless redirected).
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#
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# For example, you can run a backup of all your user accounts
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# at 5 a.m every week with:
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# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
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#
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# For more information see the manual pages of crontab(5) and cron(8)
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#
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# m h dom mon dow command
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00 11 1 * * /usr/local/bin/api-keepalive.sh <username> <password>
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```
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This will run once per month, on the 1st, at 11:00.
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That's it! Stupidly simple, and I am no longer scared of cron |