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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918 views

Daemon or crontab?

I understood that I can create a service that would run and perform certain tasks in the background. But I actually only need to execute a task that needs to be done every 5 minutes. It needs not to ...
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1answer
235 views

mythbuntu epg cron job not working

I've got a problem with my EPG grabber script 'shepherd' for the Australian EPG. These two commands below work when I type it as user mythserver but when I put them in cron the first command creates a ...
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2answers
355 views

How do I shutdown Oracle automatically every Friday at 10pm?

You install oracle database but need to shutdown at night every Friday at 10pm so that you can make backups. How would you achieve this automatically using the crontab utility? Assume that the script ...
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2answers
666 views

Anacron mailing weird errors

Since update to 11.04, I keep receiving messages from 'Anacron', with some errors. Two types of messages, actually. The first of those types is like: /etc/cron.daily/logrotate: ...
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3answers
576 views

Wallpaper change crontab jobs not working after upgrade from 8.04 to 10.04

I have a crontab job set. It is a script to change the Desktop background wallpaper every 3 minutes. It was perfectly working before upgrading from Hardy to Lucid. When upgraded to Lucid, the ...
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3answers
2k views

Need help with bash checking if computer uptime is greater than 5 minutes

I have an bash script that runs on a every minute cron. It checks to see if a necessary program is running and starts it if it is not. Occasionally it will run before the user has actually autologged ...
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2answers
1k views

How to create daily job without write access to /etc?

I don't have write permissions to /etc and its sub folders, but even do I would like to have bash script that is executed every morning. How to set it up? also when i type cron in command line I get ...
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2answers
1k views

How to append text to file every morning?

I would like to append current date to text file every morning at 7am. if the computer is turned off I would like it to be executed after its turned on.
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3answers
4k views

Trying to stop a service with cron

On my Ubuntu 11.04 server when I try to run service powernap stop as a cron job with the root user, it fails and gives me this message in syslog NAS CRON[10853]: (CRON) error (grandchild #10854 ...
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4answers
10k views

Why does apt-get fail when automated with cron?

I'm trying to use cron to automate my system updates. You can see my crontab, commands, and resulting errors below. When I run upgrades.sh as root, the script runs fine. When cron runs it, apt-get -y ...
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1answer
1k views

How to use cpulimit on ALL cron jobs?

Using Ubuntu Server an AWS micro box, so if the cpu utilization spikes AWS will virtually kill the CPU for the box (for about 30 sec). nice doesn't solve the problem, but cpulimit does (I use it in ...
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1answer
2k views

CRON is changing encoding?

I have a legacy Java program that outputs an SQL script. I then use Apache Derby to run that SQL on the target database (which is not on the same server as CRON). When run via putty, this works fine. ...
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1answer
3k views

Using curl with filename containing a dynamic date

I'm trying to upload dynamically created log file from my local box to my FTP server. This all happens in a cron job (crontab) I run every night. It creates the file using: 30 00 * * * touch ...
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1answer
237 views

Refresh database in banshee

I have a library of around 20k songs and it takes forever to banshee to index it. I would like to force a database refresh by cron. My PC starts every night to do the backup with my cloud backup ...
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1answer
2k views

Trouble with bash and crontab [duplicate]

Possible Duplicate: Reasons why crontab does not work I'm migrating some scripts from an older machine to a lucid ec2 machine. I'm sourcing a file in our ~/.bashrc and setting some ...
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2answers
214 views

Is it bad to have a long list in my crontab?

I'm toying around with building an application to display messages on the screen on a desired intervals. I want to use cron to achieve that and I am considering my options. The most naive approach ...
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1answer
163 views

Who is owner of incrond file products?

Consider this command: sudo incrontab ~/incron-config where ~/incron-config contains: /home/zetah/Documents/incoming IN_CREATE,IN_MOVED_TO /home/zetah/scripts/do_something.sh $@/$# and ...
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1answer
1k views

Can't launch gnome-terminal from anacron job

A few releases ago (lucid lynx) I wrote a backup shell script task that was executed as an anacron job every week. It worked fine then. However, It fails in natty. The idea was simple. The script ...
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2answers
6k views

Crontab not running [duplicate]

Possible Duplicate: Reasons why crontab does not work I have setup a crontab to run a shell script every minute. Here's my crontab file: * * * * * sh /var/www/stuff/public_html/recycle.sh ...
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1answer
2k views

Where is Anacron mailing job output?

I have a job that is run by anacron. In the syslog I see messages like: Apr 6 06:11:09 host anacron[1031]: Job `myJob' terminated (mailing output) but I never see that mail. If I run that same job ...
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3answers
210 views

Configure a cron job to run only if laptop is plugged in?

I'm setting up a cron job to update my nmzmail database periodically, but I'd like the cron job to execute only if my laptop is plugged in. Is there a way to do this? If there's not a built in cron ...
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2answers
419 views

Why doesn't cron complete my script?

I have a backup script (rsync via ssh) which is run by cron (configured in /etc/crontab) 0 2 * * * root /bin/bash --login /opt/aebackup/sshbackup.sh If I run it as logged in root like ...
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1answer
2k views

Why would logwatch (with cron) on stop e-mailing me daily reports?

I have logwatch configured with cron to e-mail me a daily report from my ubuntu server. Occasionally, something happens like the power goes out (which is what just happened actually) or the system ...
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1answer
417 views

Accidentally Uninstalled ubuntu-desktop and Anacron. Reinstalled. What Can I Expect?

Unfortunately when I installed the fcron package to take a look at it, I didn't realize that I was also uninstalling Ubuntu Desktop and Anacron. So, I then did apt-get install anacron ubuntu-desktop, ...
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2answers
2k views

How can I create a cron command that will execute a command inside a detached screen?

I have created a screen, but can I now somehow execute a command that will run commands in the detached screen? I do not even know if this is possible, but if it is, it will probably be something ...
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1answer
287 views

Schedule a theme change using cron

I am trying to figure out how to automatically switch to the Equinox Evolution Dawn, Light, Dusk, and midnight theme at the appropriate time of day (ie; at 6 a.m. it would switch from midnight to ...
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2answers
6k views

How to use wget with GET parameter, or redirect web?

sorry,.. I'm noob in Ubuntu ... and I'm trying to make a robots for downloading file.. i can download the zip file via web browser's address bar like this ...
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1answer
2k views

“CRON: Module is unknown” after upgrading to 10.04

I just upgraded our server to Ubuntu 10.04 and cron just stopped working. I tried to restart the server, restart cron but nothing worked for me. It just reports in /var/log/syslog: May 12 16:32:01 ...
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2answers
2k views

Issues with Java's JDBC (MySQL) for linux - Crontab job causes connection failure in java program, but when run manually is fine

So as the title states, Ive got an issue with Crontab and my Java program connecting to a remote MySQL database. The program itself is quite simple: it connects to the database, grabs two tables ...
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1answer
2k views

Is it safe to uninstall anacron?

I have my desktop system running continually without shutdown and I want to get normal times (3:01, 4:15, 5:30) for cron.(daily|weekly|monthly) jobs but when anacron is installed these jobs run at ...
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2answers
349 views

Is it possible to schedule the downloads required to upgrade?

I'd like to upgrade from 10.10 to 11.04 but my ISP has a data-cap, limiting the amount I can download. Thankfully, traffic between 2am and 8am doesn't count towards this cap, but I'm seldom awake at ...
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2answers
343 views

How to automate the following task?

Daily i wanna copy some files from a remote system and i have to put all those files in on a folder on that date say .Is it possible to automate this task? What we do presently is we log on to the ...
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2answers
168 views

How do I set time for use on a server where microseconds are important?

Lets say you have a server that stores records, and the time stamp that goes into the mysql/postgres/text-file/whatever is vital to be accurate (lets pretend it's a physics experiment, or bank ...
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1answer
1k views

Cannot get new job to run using /etc/crontab and /etc/cron.daily

I want to run a script on a daily basis, and figured that I'd use the same setup that the other cron jobs are configured on this server - by placing the script in the /etc/cron.daily folder. However, ...
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1answer
485 views

Where is my cronlog? [duplicate]

Possible Duplicate: Where is the cron / crontab log? While trying to Google this a lot of sources claims there's a cron log in /var/log but I have none. I'm fairly convinced cron has run ...
2
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1answer
148 views

gpilot-install-file in a cron job?

I have a cron job that generates some .pdb files, and I'd like to automatically queue them for installation at the next sync. Unfortunately, I haven't been able to get gpilot-install-file to work in a ...
2
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1answer
2k views

Cron user root or www-data?

I'm running a website on 10.04 and am not sure how to set up my crontab. Should I create it under root or a user such as www-data? Python, Postgres, Nginx.
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2answers
932 views

How to schedule time-of-day upgrades

I'm responsible for about 30 Ubuntu computers at a private K-8 school. We have only a 3Mbps internet connection serving the entire campus, and I would like to ensure that updates are done in the ...
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1answer
2k views

Schedule sending mail of a log file content

I have postfix mail agent installed and I've configured gmail relay and I could send mails from the terminal as below: root@statino1:~# mail -s "subject_here" my_gmail_id@gmail.com CC: <hit enter ...
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1answer
158 views

How to schedule an update?

I want to schedule my machine to run all my updates unattended at night, but this requires my authentication (which pretty much axes the unattended part). Would it be best to use a cron job or is ...
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1answer
346 views

How to download Ubuntu Server backups automatically?

I'm thinking of an investment in a new root server running ubuntu. Due to the fact, that the provider won't have extra backup-space, I need an other solution. Is it possible to download the server ...
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1answer
90 views

Can I push data from web to my Ubuntu?

I am trying to do something which involves pushing data to my Ubuntu 10.10 desktop from web (PHP) and somehow I can catch that data. Just like Push emails. Thoughts? Ideas? I know I can setup a cron ...
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1answer
1k views

Why is this rkhunter script sending empty emails?

I have started running rkhunter (a security monitoring tool) and I have finally managed to clear all of its warnings. Now, a cron job runs every day to monitor my machine. Rather than send me an ...
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2answers
932 views

How to automatically visit a website in the background after Ubuntu booted?

I wanted to know how to automatically visit a website in the background when Ubuntu loads. As far as I know w3m is for visiting web site from the console. That is why I am writing following command in ...
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5answers
9k views

What's wrong with my cron.hourly configuration?

Every hour I get an email with error like this, Subject: Cron <root@supa> root cd / && run-parts --report /etc/cron.hourly /bin/sh: root: not found Contents of /etc/crontab is as ...
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1answer
728 views

How to start a job at precise time?

I want to start a recording job at a precise time. As I understand cron only guarantees a job to be started within a minute. One possible solution is to start the cron job earlier and than wait until ...
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1answer
495 views

How to make a python script run in Anacron

I have a python script that I would like to run daily using anacron, but I haven't been able to get it to work. The script is in my home directory, and I have put a symlink to it in /etc/cron.daily/. ...
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2answers
2k views

How to interpret this crontab command?

I know that if I wrote in crontab -e following command 01 04 * * * somecommand then it will run somecommand at 4:01am on every day of every month. What happens if I wrote * * * * * somecommand? ...
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4answers
4k views

execute script after desktop loaded?

I want to execute bash script on startup that opens several terminals in different workspaces. Script works just fine if I call it from terminal, but it doesn't work if executed from crontab using ...
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1answer
2k views

How to move files over samba share with gnomevfs cli

Ok I am in the process of backing up my film collection to a NAS and I wanted to automate this as much as possible as I have to work at the same time. I am trying to setup a daily dump of ISO's ready ...