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

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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. ...
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147 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 ...
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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 ...
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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 ...
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316 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, ...
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400 views

How to create a cron which finds/kills/clears old puppet runs?

I am a new user of bash/cron, and I was given a task to create a cron which finds/kill/ and clears old puppet runs that were not successfully installed. The more help the better, but I am more or less ...
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8k 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 ...
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2k views

Why does sftp hide the log from stdout?

I have a script a.sh, which has an sftp command: echo "Starting to sftp..." sftp xxx@xxx.xxx.xxx.xx << END_SCRIPT ls mput *.csv.gz bye END_SCRIPT echo "Sftp successfully." If I run it ...
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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 ...
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3answers
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I want to set up a basic cron job that sends an email

I am running OS X 10.7 and I am learning unix commands. I would like to set up a very basic cron job that sends me an email with a certain message. How would I go about this. From what I have read, I ...
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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 ...
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188 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" > ...
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614 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: ...
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2answers
517 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 ...
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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 ...
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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 ...
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1answer
2k 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 ...
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/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 ...
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975 views

What's the purpose of having different crontabs per user?

Is it just for controlling the permissions of the script being called or does it also effect when or if the script runs? I assume if I setup a cron for a non-root user it should always run, even if I ...
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324 views

ipsec auto --status fails in cronjob

I have a server monitoring script which, among other things, checks the state of an IPSec tunnel using ipsec auto --status It works like a charm when run from the console (as root) but as soon as I ...
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1answer
258 views

How to print the next crontab tasks to be executed?

Is there some way to display a list of the approaching task executions? That is, translate this crontab: # m h dom mon dow command * * * * * imapfilter 4 20 * * Sun fgit gc -- ...
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444 views

How to update MOTD regularly?

Every week there's a new work log/to-do list at work. There's a todo script which can be used to extract my own to-do items from that. Currently this is called in ~/.bash_aliases_local, which is ...
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950 views

Start and monitor process with CRON

There is a stub application written in C. Now I want to run this application periodically, say at 11.30am daily. I thought of using the cron process but I don't know how to do it. Please help. Also ...
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3answers
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cron, every minute ram issues

I have a cronjob which runs php on a wordpres cron.php file. Its mainly used to schedule post and i believe it may refresh cache. Anyways... I run the cron job every minute. I checked out the ps ...
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Centos Crontab not responding

I was learning and experimenting with crontab today. The default editor was just too difficult for me to figure out which caused me to remove my crontab by running crontab -r. Now, when I run ...
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133 views

Testing Scripts

If I have a script called teiid.sh set to run daily by a cron job. The scripts purpose is to initialize the startup of teiid. How would I make a call to test to see the if teiid.sh is working ...
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1k views

sort at jobs chronologically

Possibly a simple solution I misplaced. How can I get the output of atq sorted chronologically, so I can easily see who's due to run next? The man page for sort doesn't have anything built-in to ...
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398 views

need portable crontab host-checking/failover logic across Linux & Cygwin

A host-ping test that always works correctly from the interactive bash command line in Cygwin, is behaving incorrectly in its own crontab--always selecting the second host--and I can't figure out why: ...
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767 views

Is there anything in unix crontab to determine this should be executed in PST/CST standard time?

There is this thing in QuartzScheduler where we can say execute this in CST/BST/ or whatever timezone. This is also good when you want to execute some jobs in certain timezones and certain jobs in ...
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2k views

How to schedule something run once using anacron?

Frequently within my scripts I schedule auxiliary tasks for later in the form: at now + 8 hours <<< "rm -f workfile.$$ >> $worklog 2>&1 " or at 11pm + $(date +%M) minutes ...
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80 views

Setting up a cronjob as a file

I want to create a cronjob at my Ubuntu server by adding/modifying a file in the /etc/cron.d folder, rather than using crontab -e as it's not too easy to automate. I've managed to make a file looking ...
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618 views

changing default shell to /bin/bash of at job scheduler like in CRON

I recently switched from 2>&1 >> to &>> Is there a way to have at use /bin/bash as the shell? By default it uses /bin/sh and the man page gives no indication how anything else ...
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Facing issue with cron on embedded linux

I have a SAM9 based board running embedded linux using buildroot package. I added the crond and crontab support to busybox from make menuconfig and built the rootfs and flashed it to my board. The ...
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1k views

What does the following kernel message mean?

The following appears /var/log/messages, what that means ? Feb 19 22:51:20 kernel: [ 187.819487] non-matching-uid symlink following attempted in sticky world-writable directory by sh (fsuid ...
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203 views

Crontab Change location

I want to set a personal crontab in another folder and executed. For example I want it in /home/project/tasks/crontab Like that it's easier to add/delete tasks. Thank you for your answers.
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Frustrating issue where neither cron nor su -c runs my job (permissions?)

Updated (and snipped) with more details below. I've set up a cron script and I'm trying to debug why it's not running. [Snipped context testing, which is all ok; see revision 2 for details] The ...
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4answers
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command for counting number of active cron jobs in crontabs

Problem statement I have 5 solaris boxes, some have Solaris 10 and some have Solaris 9. All of them have many cronjobs in their crontabs. I would like to know number of active cronjobs available, so ...
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721 views

Is crontab related to server performance?

I am using Solaris 10, and I am adding many cronjobs to my server's crontab. Currently I have 30 cronjobs in my crontab. one cronjob takes 8 hours to complete ,one other cron job takes 5 hours to ...
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Origin of the word cron?

Trying to settle a friendly argument. Is "cron" an acronym for something? Additionally, did it's current canonical name "cron" originate from something shortened for something like chronos or ...
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cifs write errors in cron job

EDIT: THE SOLUTION With Tim's help I determined that larger writes of data were failing versus smaller ones. Why they didn't fail when I ran the script interactively, I don't know...But here was the ...
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Open emacs in a terminal when editing crontab

I have setup emacs as my default editor in /etc/profile. When I want to use emacs in a terminal. I open it with the -nw option. How can I have the same behavior when doing a crontab -e preventing it ...
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6k views

List currently running cron tab and stop it

I created a cronjob, it runs for a very long time but now don't know how to stop it. Please help.
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1answer
5k views

Meaning of “* */1 * * *” cron entry?

Somehow, I am finding it difficult to understand tweaking around * parameters with cron. I wanted a job to run every hour and I used the below setting: * */1 * * * But it does not seem to do the ...
5
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2answers
5k views

How can I know when a cron job was killed or it crashed?

Usually when a cron job crash, it will leave some error messages in the log. We run shell script and some java program with cron job. Recently we found some weird thing out from the log. Obviously ...
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143 views

Can I filter how often cron emails me?

I have a few cronjobs and one of them is run every minute. I had to take a website down for two hours and it caused an error on that one specific cronjob and I got almost 120 emails in those two hours ...
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4answers
850 views

Is there any handy command line tool to manage Cron jobs?

Would someone suggest any handy command line (NOT web) tool or script which adds, enables and disables Cron jobs? I am looking, for example, for the following (or similar) behavior: sh manageCron.sh ...
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Can I change the default mail recipient on cron jobs?

I believe that if there is any output from a cronjob it is mailed to the user who the job belongs to. I think you can also add something like MAILTO=vivek@nixcraft.in at the top of the cron file to ...
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863 views

grep searchstring /etc/crontab strange behavior in BASH script

I am working on a BASH script which creates automated backups via the crontab. I am trying to use myVARIABLE=`grep backup /etc/crontab` to return lines containing "backup" if an entry has already ...
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1answer
5k views

How do I enable locate and queue the database to be built?

On a new Ubuntu 10.4 instance, I tried to use the locate command only to receive the error locate: can not stat () `/var/lib/mlocate/mlocate.db': No such file or directory from using this command ...
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74 views

App which can execute arbitrary code on different events

I've been looking for a simple activator which can execute some code when stuff happens, I haven't found anything yet. Maybe, I am not using the right keywords. It would be great if someone pointed me ...