Cron is a job scheduler that allows users to run commands periodically.

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3
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2answers
938 views

How do I check active crons?

I'm trying to hunt down a cron job (or the equivalent) which I know is running, but I can't find it in the default cron files for my system (FreeBSD / Linux / BSD). How can I tell which ones are ...
-4
votes
4answers
9k views

Cronjob for rebooting everyday

I have set this cronjob because I want my server to be rebooted everyday at 05:00 # file: /etc/cron.d/reboot * 5 * * * root reboot &> /dev/null I think it worked the first time as I was ...
2
votes
0answers
807 views

Cron file syntax checker/validator script

Does anyone know a script (bash, perl, php ...) to validate the syntax of crontab files? I found this http://www.intuitive.com/wicked/showscript.cgi?053-verifycron.sh but just Vixie cron notation is ...
1
vote
2answers
1k views

CentOS, PHP file is running from browser, not from cron daemon

I am working on CentOS. I have created a PHP file which run from browser http://mydomain.com/backupfile/dobackup.php I have added the script from crontab and made the file executable, but it is ...
5
votes
3answers
2k views

How to get which version of cron daemon is running

Background: I am working on CentOS Details # cat /proc/version Linux version 2.6.18-308.4.1.el5PAE (mockbuild@builder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-52)) #1 SMP Tue Apr 17 ...
2
votes
1answer
717 views

/etc/crontab edited via copy and paste, how to revert back?

I have made a mistake, I have edited /etc/crontab via copy and paste. And now those crontab entries are not working. [root@process ~]# cat /etc/crontab SHELL=/bin/bash ...
2
votes
2answers
6k views

Watchdog script to keep an application running

I currently use an application called MxEasy on my linux servers to display video from a couple of IP cameras. The software is rather buggy and crashes occasionally. I've wrote a script that checks to ...
-5
votes
2answers
705 views

Who can use cron? I can't help myself. Who is using cron? [closed]

I want to run cron every minute OR hour xclock. It's not that simple as I guessed:( I'll wait for your answer, sir. Maybe It'll be too late, before the right answer as 1 2 3...
1
vote
4answers
32k views

crontab -e , then 0 * * * * = every hour… Where is stored

After sudo crontab -e (it wrote "/tmp/crontab.XXXX70pN9h" 1L, 19C 1,1 All Then I saved the file. And to check..? (how? i don't know) And to check I ps -e | grep cron 29818 ? ...
2
votes
1answer
508 views

How to use crontab (Gentoo)?

First I installed and ran crontab: emerge cron crontab -e In another console, I ran man cron, but this has no examples of how to use crontab. Where can I get examples, and why are there none in the ...
1
vote
2answers
660 views

crontab and DST disagreement with different timezone

From a server hosted in Poland (UTC +01:00), is there a way I can consistently have a crontab entry run at 9am New York time (UTC -05:00)? For me this wasn't trivial since the daylight saving time ...
2
votes
1answer
3k views

Periodically download attachments from mail box

Is there a preferably CLI based program I can use to regularly (through cron for example) use to check a mailbox, and download the attachments into a folder? I have a mailbox called ...
1
vote
1answer
593 views

Cron job - permission denied creating a file

I have a cron job: #!/bin/bash fn=db.backup.$(date +%m-%d-%y).sql mysqldump -uMyUsr -pMyPass --add-drop-table dbName> $fn find ./ -name '*.Z' -type f -mtime +7 -exec rm -f {} \; I get an error: ...
0
votes
2answers
384 views

Why does this fail as crontab but works as script [duplicate]

Possible Duplicate: What’s wrong with these two cron job’s? I want to print a formatted output from a file containing lines of date, time, long number, and long number. I set LC_NUMERIC to ...
15
votes
1answer
39k views

How to redirect output to a file from within cron?

I have a backup script which I need to run at a particular time of a day so I am using cron for this task and from within cron am also trying to redirect the output of backup script to a logfile. ...
1
vote
1answer
588 views

cron to delete after executing

I have a cron job which unzips a file and executes it. The cron is set to unzip, execute and delete the .zip file after. It's executing fine but it's not deleting the file. Here's the cron: ...
3
votes
3answers
3k views

Conditional crontab command in bash script

How do I invoke a crontab command so that I can schedule to run a script with a 20 minute delay based on some condition? Edit: What if I wanted a command that schedules a script to be executed only ...
11
votes
3answers
19k views

Manually run a cron job / simulate running cron job?

I am new to cron and I want to test if cron's mailing stuff after an executed task and things like that work. Is there a more elegant way to test this, then setting a cron job to run every few ...
1
vote
1answer
417 views

Putty doesn't seem to start from python'd crontab

I have the following Python script, chmod +x'd. When I run this script from the command line and Putty has not been started, it launches putty: #!/usr/bin/env python from __future__ import ...
5
votes
2answers
295 views

How to schedule a job that depends on network availability?

I have cloned a git repository of some project. I want to automate git pull and compile the project once in a week. I am using a laptop which wont be on 24x7. Now, I cannot use cron as I should keep ...
11
votes
1answer
14k views

Why does cron silently fail to run sudo stuff in my script?

I have a script run from a non-privileged users' crontab that invokes some commands using sudo. Except it doesn't. The script runs fine but the sudo'ed commands silently fail. The script runs ...
4
votes
1answer
231 views

Emptying a directory owned by another user weekly

I have a temp directory set up where users can place whatever files they need to send to other users via HTTP. The owner of this directory is an SFTP user, and cannot run cron jobs. I have one shell ...
0
votes
1answer
577 views

cron logging but not working on some commands [duplicate]

Possible Duplicate: How can I execute date inside of a cron tab job? I have a server in Amazon EC2 that I run a backup script on with cron. However, it is not working. To test out if cron ...
5
votes
3answers
4k views

How can I ensure my cronjob will run at specified time?

I'd like to know how I can check to see if my cronjob will run at the specified time I set it at. Is there anyway I can test this without having to wait for that time? Here are my crontab -l results: ...
7
votes
3answers
2k views

Run Script once a day with systemd

I want to run a backup script 10 minutes after booting up my machine but only once a day. Is it possible to build up such scenarios with systemd?
3
votes
1answer
501 views

How do I push a Mercurial repository to BitBucket over ssh? [closed]

I created a public key for ssh and registered that key with BitBucket. I then attempted to push: $ hg push ssh://jhayward@bitbucket.org/johncharrell/[project name] pushing to ...
6
votes
3answers
3k views

What's wrong with these two cron job's?

I have the following cron jobs defined. 55 8 * * 3 /usr/bin/php /home/mark/dev/processes/customClient/events.php > /home/mark/dev/processes/customClient/events-`date +%Y-%m-%d ...
1
vote
3answers
3k views

Why isn't cron running automatically?

OS : Ubuntu 12.04 Now I want to use Backup and Whenever gem to automatic backup my database. When I connect the server by ssh as an added user to run backup perform -t my_backup,it works well.But the ...
7
votes
5answers
5k views

Check if script is started by cron, rather than invoked manually

Is there any variable that cron set when it's running a program ? If the script is running by cron, I'll skip some parts; otherwise invoke those parts. How can I know if the bash script is started by ...
2
votes
2answers
2k views

Cron to delete particular file(s) from a specific directory

I am new to shell scripting. I am trying to write a cron for unix shell that will delete some files, say after 2 weeks or after 1 month from a specific directory. /somedir1/somedir2/ if(somedir2) ...
0
votes
1answer
495 views

Mplayer cronjob doesn't work [duplicate]

Possible Duplicate: How can I execute date inside of a cron tab job? I made a cronjob to record a stream every friday between 23pm and midnight. Only somehow this doesn't seem to work. ...
4
votes
1answer
145 views

In crontab is it possible to specify a user from a variable?

I am trying to have the following cron executed with a certain user. U=`/usr/bin/w | grep -w :0 | awk '{ print $1 }'` */1 * * * * $U /opt/script.sh It seems the deamon doesn't know how to interpret ...
1
vote
1answer
3k views

Run gui application on startup

I can run a script at boot by adding the following line to my crontab: @reboot perl /path/script That works fine. But the problem arises when I try to run a gui application such as gmail notify. It ...
3
votes
1answer
2k views

Maximum Number of Entries in Crontab

If it exists, what is the maximum number of cron jobs (entries?) that can be added to a server's crontab? How do I tell? I'm on RHEL 6. I googled around, but did not see a conclusive answer -- some ...
2
votes
2answers
2k views

Python script to shutdown system doesn't work in cron

A python script to shutdown system works fine from the terminal but doesn't work when included in crontab. The script is called by cron but ends with an error 'shutdown command not found'or 'init 0 ...
33
votes
15answers
5k views

Run unix command precisely at very short intervals WITHOUT accumulating time lag over time

Question I'd like to be able to run a UNIX command precisely every second over a long time period. I need a solution, which does not lag behind after a certain time, because of the time the command ...
4
votes
2answers
310 views

crontab, instance, memory issues+spamming

I have a cronjob that runs php5 wp-cron.php every minute to update my website. However something happened and i had 30+ instance of it (31 is marked on this one dump of ps aux). It ate up my ram, ...
13
votes
2answers
12k views

how can I make cron run a job right now, for testing/debugging? without changing the schedule!

I have a cron job that is scheduled to run everyday, other than changing the schedule, is there any other way to do a test run of the command right now to see if it works as intended?
6
votes
3answers
3k views

What could cause a cron to run twice at the same moment?

I have a cron that is setup to run every Monday at 1 AM 0 1 * * 1 /script/dir/script >> /script/dir/file.log After two years of running as expected, it ran twice on June 18, with the second ...
4
votes
2answers
7k views

Cronjob to run every 30 minutes

I want to set a cronjob entry that runs a script every 30 minutes from 9:00 to 18:00 but I do not want it to run at 18:30. The script should run for the first time at 9:00 and for the last time at ...
3
votes
2answers
2k views

Bash script doesn't work as cronjob

I'm trying to get this simple bash script to work within a cronjob. It's used to generate static nginx webserver statistic pages using GoAccess. I tried everything I know to resolve this issue, it ...
1
vote
2answers
1k views

How can I get crontab to use a different PHP installation location?

I have a MAMP setup which runs PHP 5.3.5 on my Mac OS X 10.5 computer. I am trying to install a crontab that executes a PHP script, which is located on my MAMP server. I can only get the crontab to ...
11
votes
1answer
1k views

Suppress output unless non-zero exit code

What's the best way to suppress output (stdout and stderr) unless the program exits with a non-zero code? I'm thinking: quiet_success() { file=$(mktemp) if ! ( "$@" > "$file" 2>&1 ); ...
1
vote
1answer
187 views

crontab sets up user variable, redirect output, and detect connetcted network

I have three problem, all of them are about crontab. Can I access $HOME variable in crontab ? for example, use $HOME like this: PATH=$HOME/bin:$HOME/scripts:$PATH ? or * * * * * echo "test" > ...
1
vote
1answer
597 views

Crontab with SVN and Git

I have some repos which are both in SVN and Git. My username is guyfawkes, and in my home directory I have folder www which contains all my repos. In this directory I also have file update.sh: ...
2
votes
2answers
506 views

How do I run a program only once per day, while accounting for variable uptime and possible failure of program?

I need to run a command once, but only once, per day, until it succeeds. Continuous uptime cannot be expected, and program success cannot be guaranteed. This program requires network access, but not ...
3
votes
1answer
2k views

Where does the output go from `at` and `cron` jobs

Where does standard output go given there is now screen? It's not appearing in the same directory or my home directory. How could I actually figure this out given that I don't know how to run debug ...
4
votes
3answers
1k views

In linux, would it be possible to run a script every day 3 minutes later than the previous day?

My first solution to this was to execute date +%Y%m%d%H%M and put that format of numbers into a file, and run the script every minute from cron. Then if the date from the file matches the date ...
2
votes
1answer
1k views

Custom directory for cron commands

I'm using vixie cron on Debian/Ubuntu. How to set a custom directory to be read by cron? I want to lead crontab to run commands found in a series of files, e.g. /home/cron/*.cron or perfectly ...
4
votes
2answers
3k views

/etc/crontab permissions

The /etc/crontab file has the permissions: -rw-r--r-- I understand that this file is for system cron jobs and other users should not have permission to modify it. The current permissions allows all ...