How to disable everything in crontab -l?

Question

I just want to pause everything. Don't execute anything listed on crontab -l.

kubanczyk · Answer 1 · 2022-09-12T09:56:05.600

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First, back up the crontab:

crontab -l > my_cron_backup.txt

Then you can empty it:

crontab -r

To restore:

crontab my_cron_backup.txt
crontab -l

This works only for the crontab of the user who runs these commands, but it does not empty/restore crontabs of other users. My other answer is about suspending launches from all the users.

edited Sep 12 '22 at 09:56

answered Dec 14 '09 at 22:41

kubanczyk

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This is particularly helpful when `/tmp` is corrupted (and if your crontab -e uses `mktemp` in `/tmp`. – Kevin Lee Mar 23 '15 at 15:17
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+1 Finally, this is what worked for me. Thank you – Pavan Jun 04 '15 at 23:25
@alex This should be the accepted answer – Luis Ferrao Sep 07 '18 at 08:52
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`crontab -r` is what I was looking for. Thanks ! – forzagreen Feb 26 '19 at 13:48
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If you are running your cronjobs in sudo better make sure you sudo first when backing up so you get the right one. – Cesar Bielich May 24 '22 at 18:15

score 81 · Accepted Answer · answered Dec 14 '09 at 22:39

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crontab -e then comment out each line you don't want to run with #.

answered Dec 14 '09 at 22:39

gregf

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Try this with 100 jobs ... – merlin May 19 '20 at 04:40
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@merlin Use column edit move in vi/vim – whirlwin Jun 08 '20 at 13:33

score 78 · Answer 3 · answered Dec 14 '09 at 22:46

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Do you have root access? Just pause cron

sudo /etc/init.d/crond stop

Then restart it when you're ready

sudo /etc/init.d/crond start

answered Dec 14 '09 at 22:46

muffinista

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That is assuming you want to stop crontab for all users including root. The selected answer, and kubanskamac's answer would do it for just the current (desired?) user. – Kevin K Dec 15 '09 at 00:20
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our crond service had been stopped. This pointed us in right direction to check whether crond was running, and restart. – Paul May 24 '16 at 12:51
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If you're on Ubuntu you can use `sudo service cron stop` – Joel Oct 28 '16 at 11:14
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On Debian this is `/etc/init.d/cron stop`. – Faheem Mitha Jul 19 '17 at 05:52
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@Faheem on Debian nowadays it’s also `service cron stop`. – Stephen Kitt Jul 19 '17 at 08:42
on centos i did `systemctl stop crond.service` – Binyamin Feb 02 '21 at 08:02
I get `sudo: /etc/init.d/crond: command not found` – Black Sep 13 '22 at 10:23

score 13 · Answer 4 · answered Dec 15 '09 at 10:46

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If you are using vi as editor, then just enter :%s/^/#/ in command mode. In all lines (%), it substitutes (s///) the begin of line (^) with a hash (#).

answered Dec 15 '09 at 10:46

andunix

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If you are not using vi as default editor, you can "force" usage of vi like `EDITOR=vi; crontab -e`, and than you can use the trick above. – Betlista Jan 25 '13 at 11:53
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To uncomment, command is `:%s/^#//` – NP01 Aug 14 '13 at 03:18

score 6 · Answer 5 · edited Sep 12 '14 at 11:19

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Wasn't happy with the options above since they weren't one liners.

To disable crontab -l | perl -nle 's/^([^#])/# $1/;print' | crontab

To enable crontab -l | perl -nle 's/^#\s*([0-9*])/$1/;print' | crontab

usage example ( edited to show it doesn't disable comments)

$ crontab -l
# Comment
0 0 * * 0 /opt/something.sh

$ crontab -l|perl -nle 's/^([^#])/# $1/;print'|crontab
$ crontab -l
# Comment
# 0 0 * * 0 /opt/something.sh

$ crontab -l|perl -nle 's/^#\s*([0-9*])/$1/;print'|crontab
$ crontab -l
# Comment
0 0 * * 0 /opt/something.sh

Tested this on RHEL and AIX , and should work out of the box without anything needed to be installed

edited Sep 12 '14 at 11:19

HBruijn

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answered Sep 12 '14 at 10:31

segaps

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Also can look for specific details in the cronjob crontab -l | perl -nle 's/^#\s*([0-1*])/$1/;print if /.+mytexttofind.+/' – Jason Nov 06 '16 at 06:10
Could you please explain why comments are not affected? What is the pattern you use to detect them? – Sopalajo de Arrierez Dec 24 '17 at 23:39
Hm, under Debian Jessie I get the following error: `crontab: usage error: file name must be specified for replace`. It seems you have to specify a file (?) when using `crontab` without any parameters (which is `replace` by default). – fritzmg Dec 04 '18 at 14:06

score 3 · Answer 6 · answered Oct 13 '14 at 21:23

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In my limited testing, setting the shell to /bin/false works. You will still see /opt/job.sh executing in your logs, but it will be a noop:

SHELL=/bin/false

*/1 * * * *    root  /some/job.sh

answered Oct 13 '14 at 21:23

ash

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kubanczyk · Answer 7 · 2022-09-12T09:44:47.867

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In any flavor of Unix/Linux that I know of (except maybe OpenBSD):

mv /var/spool/cron  /var/spool/cron_is_disabled

This:

disables crontabs of all users
but not system /etc/crontab (/etc/cron.daily. etc.)
persists across a reboot
is a one-liner, duh :)

edited Sep 12 '22 at 09:44

answered Nov 05 '15 at 17:12

kubanczyk

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score 1 · Answer 8 · edited Jun 29 '16 at 18:23

1

I got the idea from the answer provided by @segaps

To disable:

crontab -l | awk '{print "# "$1}' | crontab

To enable:

crontab -l | cut -c 3- | crontab

The only problem with the solution provided by segaps, is that it will uncomment the jobs, that are already commented by the user.

edited Jun 29 '16 at 18:23

Joffrey

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answered Jun 29 '16 at 13:49

Sarvsav Sharma

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Disable command should be: crontab -l | awk '{print "# "$0}' | crontab – Raymond Chiu Aug 25 '20 at 08:49

score 0 · Answer 9 · answered Apr 15 '20 at 16:47

You can use the following like so:

crondisable
cronenable

crondisable some_other_user
...

The zsh code (put in your .zshrc):

ecerr () {
print -r -- "$@" >&2
}
crondisable() {
        local user="${1:-$(whoami)}"
        local cronpath="/tmp/$user.cron.tmp"
        test -e "$cronpath" && {
        ecerr "There is already a disabled crontab at $cronpath. Remove that manually if you want to proceed."
        return 1
        }
        crontab -l -u $user > "$cronpath"
        crontab -r -u $user
}
cronenable() {
        local user="${1:-$(whoami)}"
        local cronpath="/tmp/$user.cron.tmp"
        test -e "$cronpath" || {
        ecerr "No disabled cron at $cronpath"
        return 1
        }
        crontab -u $user "$cronpath"
        mv "$cronpath" "${cronpath}.bak"
}

score 0 · Answer 10 · answered Dec 13 '17 at 21:32

0

To do this, using nano as the editor:

sudo env EDITOR=nano crontab -e

then comment out each line you don't want to run with #

answered Dec 13 '17 at 21:32

Jonesome Reinstate Monica

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How to disable everything in crontab -l?

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