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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setting up anacron for version control update

I store some of my configuration files in version control. Recently I tried to setup a daily anacron job so that I won't have to manually update the files. I have never used cron or anacron before but ...
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2answers
4k views

How can I set up a php script to run via cron?

How can I set up a php script to run via cron I've created a file in the cron.d folder with the username as the file name: /etc/cron.d/username Inside of username file I placed the following cron ...
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1answer
2k views

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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1answer
976 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
3k 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
15k views

How to stop email report from Cron <root@machine> (hourly)

I'm running an Ubuntu 12.04, I've configured "ssmtp" with my gmail account and now I'm getting every hour an email with a report, this is an example: From: root <my@gmail.com> Date: 2012/8/13 ...
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2answers
2k 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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45k views

How to run a cron job using the sudo command

Is it possible to run a cron job which needs the sudo command? Like: sudo rm somefile
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1answer
346 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
391 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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3answers
13k views

How do I configure exim4 to send mail through a password protected ssl smtp mail server?

I'd like my cronjobs to be able to send mail from my home computer. My servers configure exim4 like this: dc_eximconfig_configtype='internet' dc_other_hostnames='' dc_local_interfaces='127.0.0.1' ...
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1answer
4k 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
250 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
10k views

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
693 views

Telnet output file DOES NOT WORK Correctly UNDER Crontab

I'm using the Ubuntu 10.04.4LTS, and have Ganglia installed in my computer. I used to get the Gmetad data by typing: telnet localhost 8651 > /test/test.txt or made a .sh file to run it. After ...
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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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1answer
491 views

Cron job running successfully suddenly reports script is not found

What might cause cron to suddenly report a file it is supposed to run is "not found," when the file hasn't been touched, and in fact, the entire system hasn't been touched since it last ran ...
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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
476 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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0answers
637 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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2answers
970 views

Only run CRON job if connected to specific wifi network

I am a newbie to scripting on Linux (Lubuntu), but I would like to make a script that runs a cron job only if my laptop is connected to my home wifi. Is this possible? I guess, I could do something ...
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3answers
29k views

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 ...
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1answer
1k 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
595 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
945 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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1answer
810 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
6k views

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 ...
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2answers
576 views

Set server timezone but not working with crontab and phpmyadmin

TimeZone is not working properly I am using linode server running ubuntu 12.04LTS. My Question is when i configured timezone by using dpkg reconfigure tz as IST ASIA/Calcutta. It shows correct ...
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1answer
292 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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577 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
1k 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
1k 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
1k views

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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4answers
5k views

Generic solution to prevent a long cron job from running in parallel?

I am looking for a simple and generic solution that would allow you to execute any script or application in crontab and prevent it from running twice. The solution should be independent on the ...
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4answers
1k views

Cron not able to succesfully change background

I'm running 12.04 with a custom XML background (modification on Day of Ubuntu) that changes based on time of day. I've noticed that there's a significant delay between when the changes are scheduled ...
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2answers
19k views

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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1answer
739 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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2answers
4k views

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 ...
3
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2answers
663 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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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
126 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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0answers
578 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: ...
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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
846 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
301 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
230 views

Why does mplayer freeze when running from Scheduled Tasks?

I've been trying to use Scheduled Tasks and mplayer as an alarm clock, scheduling mplayer /path/to/file.mp3 for my morning wakeup time, but whenever it reaches the scheduled time, mplayer freezes only ...
4
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1answer
1k 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 ...
11
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2answers
55k views

Script doesn't run via crontab but works fine standalone

I have a script that reminds me to restart my computer if uptime is more than, say 3 days (although its set to 0 days now just to check if the script is running as my computer has been up only over a ...