Cron is used to execute scheduled commands. It acts as a task scheduler on Linux and UNIX systems which will execute commands at specified times set by the user. Cron has a great deal of customization and is often used on server environments where common tasks are run on a regular basis.

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Why doesn't this script output to a text file when run from cron?

I have created a Shell Script as below Sample.sh echo "Hi there" I also added cron job in cron tab which is under /etc/crontab as below * * * * * /home/Sample.sh > /home/Sample.txt I have ...
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1k views

Cron service up but apparently not working

I'm trying cron in a Ubuntu VPS with a minimal install, so I had to run apt-get install cron. However, say I run crontab -e and add (as root) the following line: * * * * * date >> /root/datelog ...
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2answers
4k views

How to make a bash script generate a new filename every time it's run?

I'd like to make a .tar file of a particular directory every day of the week. The way I'd like to do it is with a bash script making a tar file every day with crontab. I was wondering, is there a ...
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2answers
3k views

crontab Suddenly Stopped Working

Ok so here is my problem, I recently updated my server and change some jsp files which are used to do automatic announcements. The crontab has all the .sh files listed within it and the .sh files run ...
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1answer
407 views

rsync password problem

I have a python script. In that, I am using rsync for data transfer between two systems. While running, it ask for password for data transfer. So that I create a password-less run by the below ...
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1answer
2k views

Why does my computer shuts down itself every morning at 6 AM?

My computer shuts down by itself at a specific time everyday 6:00am. I can't find what's causing it. I'm a long time Windows user and just recently tried Ubuntu. So I don't know anything about Linux ...
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1answer
559 views

How to start and stop a task using at command?

I want to start download using aria2c everyday at 02:00 am and stop it at 08:00 am. I know I should use at 02:00 at>aria2c .... I don't know how to tell 'at' to stop it! Actually aria2c stops ...
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1answer
5k views

How to start / stop Dropbox at a specific time

I have setup a service on my Ubuntu 10.04.4 LTS server, which works when started and stopped manually using sudo service <service> start etc. However I would like to have the service (dropbox ...
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2answers
266 views

crontab not working as expected

I'm using ubuntu 12.04 and I want to execute a script every 5 hours . I setup cron with crontab -e and putted * */5 * * * sh /home/cron_script.sh The script is executed every minute. Thanks.
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1answer
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Cron job not executing

I was making a cron job to save my Minecraft world from my ram every 5 minutes. I tested the script and it seems to be working. This is what the script looks like: #!/bin/sh ...
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1answer
1k views

Why does Ubuntu Server run both cron and atd?

From the man pages it appears both do basically the same thing, why have both running on the system at the same time? From the wording in the man pages it looks like cron will repeatedly run programs ...
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956 views

Run /etc/cron.daily/apt at a specific time (i.e. without anacron)

I want to setup a cron job to download up-to-date package only at night. But I found that the cron.daily jobs will be run by anacron if it's installed, so if my computer fails to wake-up at night to ...
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1answer
2k views

Cron not sending email notifications

I'm finishing biulding our new server, based on 12.04 32-bit desktop version. I've set up a few cron tasks, that are running as they're supposed. only, I've added the MAILTO = ...
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1answer
496 views

Cronjob not working

I have added a new line to my crontab file, but this line won't work. This is the code of my crontab file: # Music scrobbler # Every 5 minutes */5 * * * * php -f /var/www/Music/scrobble/index.php # ...
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2answers
10k views

“command not found” when running a script via cron

I want to run my script in crontab, but I have some problems... In my script I run this command: db2 connect to myDB2 This works fine when I run this as db2inst1 user, but when I run this script ...
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1answer
110 views

Crontab file is garbled! HELP!

I accidentally deleted my .bashrc file in Ubuntu 11.10. I think I restored it but I have two major issues now: Everything that I type has a red squiggly line under it in this field and the ...
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0answers
783 views

Why doesn't duply work when set as a cron job?

I have a problem with a cron job which starts but doesn't complete. Running the command manually works fine. I already read the page about cron issues and solutions here on AskUbuntu, tried the ...
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1answer
201 views

Script not working through Cron - JDK version mismatch between shell and script

I am executing a script through cron using the below command: */10 * * * * cd /nas/app/someFolder/psox; ./RunPSOX.sh >> /tmp/trial.log 2>&1 This is being executed by root user. All ...
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3answers
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How can I tell if my hourly cron job has run?

I have created a file called ntpdate in /etc/cron.hourly #!/bin/sh /usr/sbin/ntpdate-debian date > /tmp/william_tmp date > /william_tmp date > ~/william_tmp echo test I also did Chmod 755 ...
12
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1answer
2k views

What is the story behind the default times set in /etc/crontab?

To my understanding, this is the default configuration of /etc/crontab: # m h dom mon dow user command 17 * * * * root cd / && run-parts --report /etc/cron.hourly 25 6 * * * ...
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1answer
699 views

Why does cron.hourly not care about the existence of anacron?

This question came up over in Root Access. Why does the default /etc/crontab not check for existence (and executable flag) of /usr/sbin/anacron for the hourly entry? My /etc/crontab: # m h dom mon ...
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1answer
1k views

Why isn't this simple CRON job working?

I am on Ubuntu server and would like to send an email to myself every 10 minutes (as a test). The code for that is in this file: /var/www/cron-test.php To set up the cron I typed: crontab -e ...
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2answers
706 views

Cron job fails for any time other than default * * * * *

On Ubuntu 11.10 (Oneiric Ocelot), my cron job run fine if I use the default * * * * * But if I want it to run at 17 hrs or any other time, it never runs. My settings are: 00 17 * * * wget ...
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1answer
960 views

Split a large XML file by a certain node into smaller files

I've got a XML file with 1GB (about 6000000 Lines). The goal is to split this file into smaller .xml files with more or less 20000 lines each. <?xml version="1.0" encoding="UTF-8"?> ...
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3answers
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Deleting a file owned by root

Recently, a friend played a prank on my pc and now I have a file sitting on my desktop called 'hardcore_porn_xxx'. The problem is it does not go away by a simple delete. I'm new to linux so any help ...
3
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1answer
417 views

Good workflow for updating R modules around R-cran updates?

I like that R updates frequently to give me the best new packages, but it does seem to pose a problem for my R scripts on cron schedules. I noticed that every time ubuntu updater updates my r-base ...
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1answer
396 views

Cron reinstallation

Can cron be reinstalled? If so, how to take cron job backups created by system and applications like postfix, apache etc., Now after taking backups how to reinstall cron?
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2k views

In what order do cron jobs with the same schedule run?

Let's say that I have the following cron jobs: * * * * * /path/to/taskB * * * * * /path/to/taskC * * * * * /path/to/taskA Is there any guarantee to the order in which they will be run? I've seen ...
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1answer
2k views

How can I prevent two shell scripts running at the same time?

I have a tar backup script that runs once a month. It runs at night through cron. I also have a power schedule that reboots the server at 4.15 every night. The problem is that the server reboots ...
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2answers
768 views

Taking timely screenshots of particular sites

I have a website where I have to take weekly screen shots of sister sites. I was wondering how this maybe done. I had obtained the code for taking screen shots but have no idea how to open up the ...
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2answers
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How to get updated IP address mailed to me in DNSExit?

I'm using DNSExit on my Ubuntu server (Natty 11.04) and have installed the ipUpdate rpm file and did an apt-get install for chkconfig to enable the ipUpdate. I'd like to get an email whenever the IP ...
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2answers
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Crontab not working

I know that this was asked several times, but I don't know what to do... I've tried all the solutions proposed on AskUbuntu, but with no results... So... I have this shell script in my home ...
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2answers
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Mutt runng from Crontab

I have a bash script that is sending an email through command line mutt. This bash script is being called from a cron job (setup using crontab -e because of permissions needed to do all items in the ...
2
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1answer
809 views

Cron job not executing?

I'm trying to execute a PHP script every two minutes on my server, but it doesn't seem to be working. I'm using the following cron job: 2 * * * * /usr/bin/php ...
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1answer
4k views

Run Java application as Cron job

I've tried everything I can think and searched high and low for solutions of but I can't get JAVA_HOME into cron to run anything java periodically. In terminal java -version gives me everything ...
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1answer
4k views

Cron not running scripts

I have looked for several reasons that could cause my problem without luck. The issue seems to be extremely particular: my server running LTS 10.04 is not correctly running scripts relating to ...
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1answer
127 views

Is there a way to schedule aptd to check for updates only at certain times?

On Ubuntu 12.04 I've noticed that aptd sometimes uses 100% of a CPU and tends to slow down my whole laptop. I wasn't installing any packages so I'm assuming that this is the automatic update check. ...
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1answer
489 views

How to run a cron job that relies on .Xauthority?

I want to take a screenshot every five minutes with 'scrot'. To do this over a SSH connection, I can either run ssh -X user@server while true; do scrot -z; sleep 300; done OR (after manually check ...
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581 views

Is wake up from standby possible via script or schedule? [duplicate]

Is it possible to cause Ubuntu to resume from standby or sleep mode to run a scheduled task like at job/crontab? (hibernation seems to be ruled out in another question) Can a script be written that: ...
2
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1answer
1k views

How to check when was the last time anacron successfully run?

How can I check when was the last time anacron completed all the daily/weekly/monthly jobs? I understand that the timestamps at /var/spool/anacron are the times anacron started, but it can be that the ...
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1answer
2k views

run .profile function as cron job

In the .profile file of the root user I have defined a function, e.g. function printDate() { date } I want to run this function every minute and append the output to cron.log. I tried adding the ...
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2answers
3k views

How to control output from crontab?

I am trying to run a test case via automation testing (sahi) , so I am running it repeatedly after 1 hour (via crontab). What I want is that whenever my test case fails i should receive the email ...
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3answers
1k views

Crontab -e gives me error messages

I get a bunch of error messages when I run crontab -e Here are the error messages. And here is my crontab file under `/usr/bin/': # /etc/crontab: system-wide crontab # Unlike any other crontab you ...
5
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1answer
710 views

What is the easiest way to set up a cron job?

Every time I set up a cron job there is something wrong with it and I spend a lot of time trouble shooting it. I use Ubuntu and I would like to know what tools exist to make my life easier when ...
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1answer
332 views

Scheduled tasks won't start

I am quite new to the world of Ubuntu (11.04 is my version), so please bear with me if I do not give all the necessary details to help you help me. I constantly record radio streaming on the Internet ...
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2answers
2k views

crontab command not run

I'm trying to get execute a cron job everyday at noon but i can't get it to run. To test it i even tried something like a simple create command but it never runs, it seems as if the file isn't even ...
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0answers
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logcheck: (CRON) error (grandchild #4266 failed with exit status 127) [closed]

for my Ubuntu 10.04 LTS server, logcheck send me this log: Nov 14 08:10:01 servername CRON[4265]: (CRON) error (grandchild #4266 failed with exit status 127) Nov 14 08:10:01 servername CRON[4264]: ...
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1answer
528 views

Managing cron.*

I see that Ubuntu uses /etc/cron.{daily,weekly,monthly} for cron jobs. I also see that some things, like updatedb from mlocate, put their jobs there: $ dpkg -L mlocate|grep y/m ...
2
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1answer
391 views

Is it necessary to monitor cron/anacron?

I use Ubuntu at home for my personal matters, not as a "server". I shut down my computer two or three times a day and there aren't any fixed usage times. I understand that there are automated tasks ...
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2answers
249 views

How can I automate the backing up of cron jobs?

In the even of a crash I realize that I may not be backing up system and user cron jobs. How can I automate the backing up of my systems cron jobs?