fix crontabe
This commit is contained in:
parent
28a5f03a60
commit
34ee9055eb
@ -4,32 +4,26 @@ tags: [ "Documentation", "Basics" ]
|
||||
---
|
||||
# Cron
|
||||
|
||||
Various services from cron exist, e.g.
|
||||
The crontab program might have various names, like `cronie` or `crond`.
|
||||
|
||||
> sudo apt -y install cron
|
||||
> sudo apt search -n ^cron
|
||||
|
||||
Start the cronie with
|
||||
Once installed, search for the service name, and start it.
|
||||
|
||||
> sudo systemctl list-unit-files | grep cron
|
||||
|
||||
> sudo systemctl enable --now cron
|
||||
|
||||
Specify a cron job with:
|
||||
You can *e*dit your crontab with:
|
||||
|
||||
> cron -e
|
||||
> crontab -e
|
||||
|
||||
You can run a script with:
|
||||
|
||||
*/10 * * * * /home/pi/script.sh
|
||||
```
|
||||
|
||||
... which would run every 10 minutes.
|
||||
|
||||
To run something as root, do:
|
||||
|
||||
> sudo crontab -e
|
||||
|
||||
For example, you can update the database, meaning searches with 'locate' command will be faster.
|
||||
|
||||
> */30 * * * * /usr/bin/updatedb
|
||||
39 */3 * * * /usr/bin/updatedb
|
||||
|
||||
```
|
||||
## Syntax
|
||||
|
||||
`* * * * *`
|
||||
@ -49,9 +43,70 @@ Doing the same thing, but only in February, would be:
|
||||
|
||||
`0 15 * 2 7`
|
||||
|
||||
# Testing with runparts
|
||||
### Full Paths
|
||||
|
||||
Executing something requires the full path to where it is, so you cannot simply use `apt update -y`, because cron does not know where `apt` is.
|
||||
Instead, find out where it is:
|
||||
|
||||
> type -P apt
|
||||
|
||||
`/usr/bin/apt`
|
||||
|
||||
Then put that into the crontab:
|
||||
|
||||
> sudo crontab -e
|
||||
|
||||
`40 */3 * * * /usr/bin/apt update -y`
|
||||
|
||||
This will run `apt update -y` as root every 3 hours, at 40 minutes past the hour, e.g. 00:40, 03:40, 06:40.
|
||||
|
||||
## Directories
|
||||
|
||||
You can execute a script as root by putting it into a directory, instead of in the tab.
|
||||
Look at the available cron directories:
|
||||
|
||||
> ls /etc/cron.\*
|
||||
|
||||
### Testing with runparts
|
||||
|
||||
Run-parts runs all executable scripts in a directory.
|
||||
|
||||
> run-parts /etc/cron.hourly
|
||||
|
||||
## Tips
|
||||
|
||||
### Variables
|
||||
|
||||
Add your `$HOME` to crontab to use scripts.
|
||||
First add `HOME=/home/user`, then you can use syntax like this:
|
||||
|
||||
0 * * * * $HOME/.scripts/myScript.sh
|
||||
|
||||
*Remember to test the script by executing that line first*:
|
||||
|
||||
> $HOME/.scripts/myScript.sh
|
||||
|
||||
You can also add your regular path to your crontab as a variable (see example below).
|
||||
If you're using vim as the editor, just run this at the top of your crontab:
|
||||
|
||||
> :r!echo $PATH
|
||||
|
||||
### Location
|
||||
|
||||
The crontab files are in `/var/spool/cron/`, so you can backup or restore them.
|
||||
|
||||
# Example
|
||||
|
||||
```
|
||||
HOME=/home/user
|
||||
PATH=/usr/condabin:/usr/local/sbin:/usr/local/bin:/usr/bin:/usr/bin/site_perl:/usr/bin/vendor_perl:/usr/bin/core_perl:/home/user/.local/bin:/home/user/.scripts/:/home/user/.local/bin:/home/user/.scripts/
|
||||
|
||||
1 0 1 * * /usr/bin/mkdir -p $HOME/arc/$(date +%Y/%m)
|
||||
|
||||
18 0 1 */3 * $HOME/.scripts/mail-clean.sh
|
||||
|
||||
* * * * * ping -c 1 home || mail-pull.sh
|
||||
|
||||
50 18 * * * /usr/bin/timeout 30m /usr/bin/syncthing
|
||||
|
||||
```
|
||||
|
@ -1,33 +0,0 @@
|
||||
---
|
||||
title: "cronie"
|
||||
tags: [ "Documentation", "System" ]
|
||||
---
|
||||
|
||||
Various services from cron exist, e.g.
|
||||
|
||||
> sudo apt -y install cronie
|
||||
|
||||
start the cronie with
|
||||
|
||||
> sudo Systemctl start cronie
|
||||
|
||||
start a cron with
|
||||
|
||||
> cron -e
|
||||
|
||||
You can run a script with:
|
||||
|
||||
*/10 * * * * /home/pi/script.sh
|
||||
|
||||
... which would run every 10 minutes.
|
||||
|
||||
To run something as root, do:
|
||||
|
||||
> sudo crontab -e
|
||||
|
||||
For example, you can update the database, meaning searches with 'locate' command will be faster.
|
||||
|
||||
> */30 * * * * /usr/bin/updatedb
|
||||
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user