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How can I stop a cron job which is currently running?

nhinkle
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    The three answers below interpret this question in three ways. @GURU, could you please clarify what you would like to do? Would you like to kill a process started by cron that is now running, or would you like to prevent the job running in the future? – jcrawfordor Jul 29 '11 at 03:51

11 Answers11

44

You can do this the same way you'd stop any process.

To stop a currently running cron job, you can do one of the following:

pkill process-name

or if you know the PID (you can determine it by running ps):

kill 1234

(substituting the actual PID)

Dennis Williamson
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    how to list which currently running cron jobs ? – UWU_SANDUN Sep 25 '17 at 05:49
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    @UWU_SANDUN: You can use `pgrep` or `grep` the output of `ps`. There's nothing special about a process run from `cron`. You would just search for the process under its own name. You can also do `ps fauxww | grep -A 1 '[C]RON'` and lines below the line(s) will show jobs being run by `cron`. You can adjust the number 1 higher to see subprocesses if any. – Dennis Williamson Sep 25 '17 at 13:26
  • Note you must be running cygwin as admin to kill processes. See [here](https://stackoverflow.com/q/4090301/6854489) for more info on that. – takanuva15 Dec 22 '17 at 16:56
  • Using Ubuntu I typed what @takanuva15 suggested, `ps fauxww | grep -A 1 '[C]RON'`. This lists the current cron jobs running, so thereafter you can note the PID down and execute `# kill -9 PID`. Thanks! – joninx Nov 05 '18 at 08:58
  • @russellhoff: `-9` should only be used as a last resort because it prevents the process from doing any cleanup as it exits. – Dennis Williamson Nov 05 '18 at 14:04
  • On mac I needed to do `ps -A` to show the cron job – MichaelChirico Sep 05 '19 at 03:36
27

Strange, no one has mentioned this method:

$ crontab -e

In the opened editor, delete line of the task you want to stop or insert a # sign, save and exit

e.g.

before

* * * * * some_script1
* * * * * some_script2

after

* * * * * some_script1
#* * * * * some_script2

or 

* * * * * some_script1

restart the service after making changes by

sudo service cron reload
sinapan
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laike9m
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    This doesn't stop a currently running cron job, it stops future cron jobs that will be launch by cron. – Ivan Nov 19 '16 at 17:35
19

To stop running cron job .First get the process id of your command with

top -p $(pgrep -d',' your_command)

eg:-

top -p $(pgrep -d',' httpd)

and run

kill PID replace PID with process id

Miqdad Ali
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13

If you are using Redhat (RHEL)/Fedora Core/Cent OS Linux use the following command : 

/etc/init.d/crond stop

If you are using Debian or Ubuntu Linux the following command : 

/etc/init.d/cron stop

P.S : You should be root to do these things

Navaneeth Sen
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    i think it stops all crons .to stop particular cron may i know the command –  Jan 12 '11 at 07:24
  • can u pls suggest any command sen –  Jan 12 '11 at 07:27
  • I dont think it is possible in a straight way.. Maybe we should go for a hack. – Navaneeth Sen Jan 12 '11 at 07:29
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    This stops the `crond` daemon, does it also stop anything it spawned? You also generally always want `crond` running on a typical Linux system; there's a lot that usually depends on it running. – LawrenceC Dec 30 '20 at 16:31
8

First type ps aux to see what all processes are running.

Then note down the PID of each process you want to stop

Then type

kill {PID} for each process.

Also do have a look at these links (superuser links) :

Verify-that-a-cron-job-has-completed

ps-aux-output-meaning

Community
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Gaurav Sharma
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3

You can edit the cron table and comment out the task in question. Switch to the user that controls the task, export your editor of choice into the environment, then use crontab -l:

$ su - root
...
# EDITOR=vi; export EDITOR
# crontab -l
Gaff
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mfe
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    That lists the crontab. Use `crontab -e` to edit it. For systems that have it, it's preferable to use `sudo` instead of `su`. Also, `crontab -e` would work for the user (or root) crontab, but not the system crontab (e.g. `/etc/cron*`). – Dennis Williamson Jan 12 '11 at 11:40
2

If you want to remove all the crontabs that are running (the commands will be lost):

crontab -r

... or If you want to stop some commands on crontab:

  1. Open crontab to edit:
 crontab -e
  1. Comment the commands in the crontab that needs to be stopped and save it. You can comment using '#'.
Hosana Gomes
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Crescent
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2

This is my take on this, which I use from time to time.

First, let's find the process IDs of the processes cron has started by using:

systemctl status cron

This will give you a nice little process tree.

Each process' ID are the numbers displayed to the left of the process' name.

So, if my process ID for a process started by cron is 2234225, then I'll simply go:

kill 2234225

I can check either with:

systemctl status cron

or

top

that the process has been terminated.

Just remember, if the process in question is set to be started as defined by the crontab

crontab -e

then, the process in question will become activated again, just with a different process ID.

ChaotiX66
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  • Something like `ps ax | grep $PID` is far more functional than using top to check for processes, especially when there are more than a dozen. – mikebabcock Dec 30 '20 at 19:53
1

Working for me for linux

pkill -9 crontab

Kills all process having process name crontab

Abdul Saleem
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0

First of all check the working process with this command.

ps -o pid,sess,cmd afx | egrep "( |/)cron( -f)?$"

This command's output is

599  599 cron
4288  599 \_ CRON

and now kill the process with this command 

pkill -s 4288
aemre
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If you are using Redhat (RHEL)/Fedora Core/Cent OS Linux use the following command :

$ sudo systemctl status crond

If you are using Debian or Ubuntu Linux the following command :

$ sudo systemctl status cron

GoYun.Info
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