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

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Running cron script with lynx fails to work

I'm trying to automate a login process that can only be done through a browser. I am using the lynx browser to script the actions required to do this. Lynx does this by dumping a user's keystrokes ...
2
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1answer
611 views

where does Cron look for the default mail binary?

I have setup Cron Jobs to run inside a Chroot Environment, depending on the User/Group; I have noticed that these cron jobs, running inside the chroot environment, fail to send any mail. Log files ...
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141 views

Write log for a false statement of an if condition which returns exit 2

I have a script running every 5 mins with two exits in a condition clause. #!/bin/bash date=$(date +%Y) if [ $date -eq '2014' ] then echo "Current year is $date" exit 0 else echo "Current ...
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2answers
4k views

Script runs manually but not from cron

As per the monitoring of my mysql replication status. I wrote a simple shell script with the following code #!/bin/bash date > /tmp/mysql_repl_status.txt cd /usr/bin/ "/usr/bin/mysql" "-e" "SHOW ...
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3answers
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Crontab job not emailing on failure

I have a cron job on Debian: 1 * * * * /home/paradroid/bin/myscript.sh >/dev/null There is an installed and configured MTA, and I have received emails when the script has a syntax error, so I ...
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Execution order with multiple commands

I'm relatively new to Linux and I'm working on a CronTab for scheduled backups. I figured out how to do multiple sequential jobs with ; and &&, but I'm unsure how the dependency affects the ...
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2answers
238 views

Where is the cron information stored on my gentoo system?

I have a Linux gentoo system, which performs a cronjob every day at 3:10 in the morning. However, no file in /etc contains any related information to this particular cronjob, and the result of crontab ...
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1answer
2k views

Crontab does not run?

crontab -e 0 */4 * * * root /usr/bin/rsnapshot hourly 30 3 * * * root /usr/bin/rsnapshot daily 0 3 * * 1 root /usr/bin/rsnapshot weekly 30 2 1 * * root /usr/bin/rsnapshot monthly tail /var/log/...
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3answers
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Custom crontab does not work (FreeBSD)

I created file crontab.custom with: */1 * * * * /home/username/data/www/run.sh And run.sh contains: php script.php After this I run this command crontab crontab.custom. Now crontab -l ...
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2answers
5k views

create a cronjob to run php script

I've created a cronjob in Xubuntu to run a PHP script in every 5 minutes. I did it as follows. I entered the following command: $ crontab -e Then entered the following: */5 * * * * /usr/bin/php /...
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5answers
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How can I use cron to display messages on the screen via notify-send

I am toying around with notify-send and cron (on an Arch machine) and I can't figure out a way to combine them: I tried the solution given here and here, but neither worked. How can I use them? EDIT:...
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1answer
287 views

Cron spamming because of renice [closed]

I have a bash script that I execute using cron. The script begins like this: #! /bin/bash DIR=/home/pi/bin/run renice 19 -p $$ ionice -c 3 -p $$ : Now, every time cron runs this script it sends ...
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why doesn't 0 0 * * 1 root hostname >> /tmp/hostname.txt work as a crontab?

0 0 * * 1 root hostname >> /tmp/hostname.txt The above cron entry should run midnight on monday and create a file in /tmp called hostname.txt with the output of the hostname command. But it is ...
2
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1answer
472 views

How do I set cron to run on background?

I am on ubuntu 12.04 and following this tutorial. I want to setup cron to run in the background but I don't have a chckconfig in sbin so I can't run sudo /sbin/chkconfig crond on I am fairly new to ...
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1answer
336 views

Shell script and crontab to capture file size, name and date in a CSV file and then send via email?

I have a number of zip files in a certain folder. I want to capture file name and the size of the files in a CSV format in day wise and put it in crontab so I can report on a daily basis, and then ...
2
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1answer
626 views

Logrotate behaving unexpectedly

Find below the logrotate configuration that I'm using /usr/local/nagios/var/nagios.log { copytruncate daily rotate 7 compress missingok size 100M } And I could notice that ...
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1answer
733 views

Crontab suspicious activity

I tried using crontab -l from my terminal as root, it showed no crontab for root. So I tried crontab -e, it returns the following no crontab for root - using an empty one 888 and then the ...
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1answer
136 views

XML command line tool postgres

I have an XML files to read and load into database daily at night (cron) So i planed to do this in a batch. Is there any command line tool to : 1. Create a postgres schema using an XSD file? 2. ...
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670 views

Using gpg-agent to decrypt password in cron job

I have two scripts that both need to decrypt passwords using gpg-agent. Both of them run fine when launched from the terminal. The problem is that when run via cron, they both fail with these messages:...
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1answer
2k views

debian7 cron.allow & cron.deny files

Almost 3 weeks that, in my downtime, I try to find out where the files cron.allow & cron.deny are located in debian7 distro. No way, it seems that by default they are not in the system. 'Just' ...
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4answers
1k views

Path independent shebangs

I have a script that I want to be able to run in two machines. These two machines get copies of the script from the same git repository. The script needs to run with the right interpreter (e.g. zsh). ...
5
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1answer
719 views

BASH_ENV and cron jobs

I have several questions related to non-interactive, non-login shells and cron jobs. Q1. I have read that non-interactive, non-login shells only "load" $BASH_ENV. What does this exactly mean? Does ...
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0answers
214 views

Fetching all Git repositories in the background

I'm thinking about setting up a cronjob for fetching all my repositories every once in a while, to have the current status ready in case I'm offline. Something like the following (wrapped for better ...
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2answers
2k views

Logrotate doesnt start proftpd triggerd by cronjob

Im currently running of ideas. The proftpd doesn't restart, if logrotate is triggered by the cron task. Logrotate rotates all logfiles stops proftpd but does not start proftpd again. If i force the ...
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268 views

filter cron emails through procmail?

I'm using postfix/mutt/procmail on a Linux/Debian and I've some trouble filtering cron emails with procmail, I just want to move them to the cron/ maildir directory, but no lucky till now. I've ...
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1answer
388 views

How to force crontab to check for changed files

I have a gentoo Linux system in which I am logged in as root. How can I force crontab to read new/changed files in /etc/cron.d immedeately, so that even a new cronjob is executed if even only seconds ...
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1answer
1k views

Script to check a folder, print the files then delete those files

I am looking for some guidance on creating a script that will check a specific folder, print all documents (if any) and then delete those documents. I would also like to run this script as a cron job. ...
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1answer
71 views

Conflict between cron.deny and allow who wins?

which one wins in conflict deny or allow? Is the behavior the same for hosts.allow and all the other similar files?
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3answers
1k views

Bash script to delete a file called index.html recursively

I need a bash script (not sure how to write the actual .sh file) which I could set to be run by cron every minute and that would delete files with the name index.html that are in a specific directory ...
2
votes
1answer
432 views

kill process in script while writing file behavior

in my php script which runs as a cron job, I have foreach($sites as $site) { exec('./wkhtmltoimage-amd64 ' . $site . ' somefile.png'); exec('./zopflipng -y somefile.png somefile.png'); } ...
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2answers
61 views

cronjob time 13 * * * *

It surely going to sound like a silly question but i wanted to have a confirm about that crontab time 13 * * * * does it really mean to launch at the 13th minute of every hr of every day of every ...
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System Crontab or Root Crontab

System crontab: /etc/crontab Root crontab: sudo crontab -u root -e Which way is preferred? As they all run tasks within administration privilege.
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2answers
3k views

Automating backups run from a bash script in Linux the right way

I have a bash script I wrote to backup a Moodle installation. It works fine, I've tested the backups, but there's a problem with it; when I do the backups, since I have to use sudo to type the ...
2
votes
1answer
6k views

Executing PHP with CronJobs in CentOS 6.4 not working?

So I've spent around 2-3 hours now and some times researching, I found several of the same responses online but none seem to work! I'm trying to execute a PHP script every minute (as a test), but it ...
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1answer
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How to set up a cron entry that runs at 00 and 30 after the hour?

I have a cron entry that runs every 30 minutes - */30 * * * * /home/myuser/myscripts.sh How to set this up such that it runs exactly at 30 minute intervals but also exactly at (for example) 3:00 ...
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2answers
742 views

Running a cron job from another shell

I would like cron to run a script from a specific shell (Zsh). I thought the following would work: 00 02 * * * exec zsh; /path/to/script.sh but apparently it doesn't, why? This also made me wonder,...
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32 views

How to block the user for a certain amount of time

Suppose, I am working in X environment, and I want to have an obligatory periodic rest. Is it possible to setup a root cron job, that will block my user for 5 minutes every 45 minutes? I am using ...
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1answer
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Why do deleted files continually reappear?

I've been having a strange issue recently, where I would delete files from a location (i.e. Desktop), and then empty the Trash. However, a day or so later (I'm not sure exactly what triggers it), the ...
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why daily cron isn't running on CentOS 6?

I have a daily cronjob set up on CentOS 6 OS which should look after the log rotation job. The file is /etc/cron.daily/logrotate and it's contents are #!/bin/sh /usr/sbin/logrotate /etc/logrotate....
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1answer
241 views

security concern around adding cron user to web application group

I have a permissions issue on my CentOS 5.6 machine with regards to the cron user. On my test/staging environment my cron user (picco-cron) is a member of one group - picco-cron, as below: [crmpicco@...
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1answer
742 views

Why CRONTAB tasks are lost when quit Putty session? [closed]

I logged to remote computer, running under Solaris, using Putty and added some jobs to be run by cron. When I quit console and logged once again all jobs was lost. crontab -l myuser How do I ...
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1answer
1k views

automate updates with a bash script and cron

I'm trying to automatize the updates of debian system, without making upgrades. Then i'll send an e-mail to me, everytime there is an upgrade available. I've tryied to do it with cron-apt, but i ...
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0answers
682 views

CRON Permission Denied [closed]

I have a Debian 7. 3 Server with WebMin installed. I configured a cron job to run every minute as root user, so I run the command crontab -l when I'm logged in as root it shows: * * * * * /usr/bin/...
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4answers
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Crontab not working

I'm trying execute a basic shutdown crontab to run M-F at 10PM. So I did the following: sudo crontab -e Once inside of the crontab I added the following line: 0 22 * * 1-5 shutdown now The job ...
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1answer
372 views

How could I signal to a cron job to skip runs?

I have a cron job that runs every X mins and that I would like to have a way to "signal" it not to do anything if needed. Is there a standard way for this? The only idea I had is to check some ...
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2answers
650 views

Does cron know that the instance to be scheduled is already running?

I was wondering if we add a job in the crontab e.g. to run every 5 mins and the job does not actually manage to finish in 5 mins, does the cron daemon know that the previous instance is already ...
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2answers
617 views

Crontab not triggered

I have a program written in C with OpenCV. It captures an image from the webcam and saves on the disk with the name given as an argument. I want to trigger it every minute, thus I inserted the ...
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1answer
3k views

Getting a Bad Hour Error in crontab

I am getting Bad Hour error for below peice of code in crontab */05 17-05 * * * wget -q -O /dev/null "http://abcd/cron/abcd" Is there any issue with this. I want the cron to run from evening 5 PM ...
0
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1answer
2k views

Cron task starts at 5:30 and runs every 5 mins once

I want to run a crontab cron job which start at 5:30 AM and runs every 5 mins. How do i set it up in Linux? I am able to give like below. But how do i make it 5:30 ? */05 5-16 * * *
3
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1answer
392 views

Accidentally typed crontab with just the dash

What happens when I type just "crontab -"? The "e" didn't take before I hit Enter. It just moved the cursor to the next line and I had to Ctrl+C to exit, but I'm not sure what it did exactly. I'm on ...