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

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Why are new cronjobs ignored unless crond is restarted in SLES?

I added a new cronjob with a user (SUSE LINUX Enterprise Server 9.4): # su - XXX $ crontab -e and this is what I added: * * * * * echo `date` >> /home/XXX/a.txt but the a.txt isn't ...
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1answer
451 views

Cron Job Clean Directory

How is it possible to delete files older than 14 days in a folder using a cron job? Everything I have tried so far hasn't worked.
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3answers
2k views

cron: bash syntax not working

I am trying to add following command to crontab: I=1; for X in $(/bin/ls -r /var/tmp/*); do [ $((I++)) -le 28 ] && echo "lower" || echo "higher"; done When executed on the command line (in ...
2
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1answer
411 views

Cronjob output to log

I'm using a script for testing broadband speed and I would like to set up a cronjob for testing every n minutes and output to a file. The command to launch it from a shell console and append to ...
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2answers
12k views

What is wrong with my cron job?

I'm new to linux, and was told I could use a feature called cron job to run a python script I made execute every 10 minutes. Problem is the the python script isn't running. There doesn't seem to be a ...
0
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1answer
146 views

run-parts ignores jobs.deny

I use run-parts to run all scripts under a directory,the same way crontab does. But the jobs deny and jobs allow don't block any of the scripts in the directory. rajeevs@rajeev:/home/rajeevs/test$: ...
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4answers
5k views

How to display a (zenity/GUI) dialog to the user after a root cron task has completed

I have a simple periodic cron task that must run as root. I want to use Zenity (or similar) to display a GUI informational dialog to user 1000 (or logged in user or all users) when the cron task ...
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2answers
18k views

What are the permissions of a cron job?

When a cron job runs with what privilege does it execute? I'm not sure about that. Is it with the same privileges of the user that added it via crontab -e?
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1answer
3k views

List of modified files of the past 24 hours

Is there a reliable way to have a system that mails me the list of files that were modified in the past 24 hours inside a set of directories? (like /home/*/public_html/* and /home/*/*domains/*)
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1answer
2k views

Cron does not print to syslog

I have following crontab file - # /etc/crontab: system-wide crontab # Unlike any other crontab you don't have to run the `crontab' # command to install the new version when you edit this file # and ...
5
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1answer
6k views

Cron job does not fire up after a timezone change

I've tried eliminating many of the common errors, 1) ensuring that the PATHs are available for cron 2) there is an endline at the end of crontab file 3) the timezone is set-up by: cd /etc cp ...
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2answers
1k views

command not running in cron (systemctl suspend)

I have this cronjob set : * * * * * /usr/bin/systemctl suspend And it is not working. But I can run it in a shell and it works. I don't understand what could be not working. EDIT Redirecting error ...
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1answer
2k views

How is cron scheduling actually implemented and makes sure scripts run on time?

I want to ask about cron jobs. OK, we place the scripts in the crontab and the cron daemon executes them. Now if I understand this, each minute, cron checks the crontab of each user and executes the ...
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5answers
8k views

Run script in a non interactive shell?

I have a cron job that is running a script. When I run the script via an interactive shell (ssh'ed to bash) it works fine. When the script runs by itself via cron it fails. My guess is that it is ...
5
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3answers
5k views

Cron allowed special character “L” for “Last day of the month” on Debian

I'd like to know if L is one of the allowed special characters on Debian's cron implementation? I'm trying to set up a cron to run on the last day of every month. From the cron entry on wikipedia: ...
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3answers
3k views

What could cause a cron to run twice at the same moment?

I have a cron that is setup to run every Monday at 1 AM 0 1 * * 1 /script/dir/script >> /script/dir/file.log After two years of running as expected, it ran twice on June 18, with the second ...
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1answer
169 views

Get system notification at a certain time?

Is there a way, in Linux or FreeBSD, to receive notification from system at a specified time? I'm thinking something in like of what inotify in Linux does for filesystem events. There IS a way to ...
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1answer
760 views

Cron automated bash script to run run 1 bash script then another, plus integrity check

So I have a custom in-house app developed by a 3rd party. When the app is running, I can verify it is running with the "screen -ls" command. As long as screens are running for rails and freeswitch ...
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2answers
2k views

setting a cronjob in IST time

I am trying to set a cronjob run in a different timezone. I've googled a lot and found editing /etc/default/cron is the way to go. But this file is deprecated and I see the following message, so I ...
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2answers
5k views

Scp doesn't work in cron

Yeah, I know it's classic. I've googled it all around, but still it doesn't work. I have the following script: #First go to SVN repo folder cd $svnrepos # Just make sure we have write access to ...
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0answers
30 views

Is there something as flexible as crontab for user-level autostarts? [duplicate]

I'm looking for a flexible per-user initialisation tool to kick off user daemons when the system (re-)boots. I suppose something similar to crontab would be great, which works for every user ...
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1answer
276 views

How to figure out what is performing scheduled server reboots?

I'm helping a friend with a server and it appears the server reboots every week on Sunday night. How can I figure out what is causing is the server to reboot? Aside from rebooting, the server appears ...
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1answer
302 views

Launch 2 celery processes via cron

I'm trying to chain some commands to periodically check/launch two processes via cron (I'm on a shared host, can't change things around). After a lot of googling around, all the things I've done don't ...
3
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1answer
1k views

How to add crontab in FreeBSD

I am trying to add a job to my crontab in FreeBSD but it is not working : I have used this to add the job: sudo crontab -e -u vaibhav @daily /home/vaibhav/applications/comparison/scrapy but it is ...
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2answers
2k views

Run a cron job every minute, meaning of syntax [duplicate]

I read somewhere that you can add a cron job to run every minute like this: #min hour day month weekday command */1 * * * * <your command> What does the /1 part mean? Can I ...
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5answers
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Using the system date / time in a Cron Script

I'm setting up a Cronjob that will backup a MySQL database I have in my server, but I don't want it to keep overwriting the same file over and over again. Instead, I want to have an array of backups ...
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1answer
222 views

Script to restart the application

I need to write a script for the below scenario in Linux: Run a cron every 5 minutes. grep the application log file to see if we can see the pattern "ORA-". If we see this pattern: stop the ...
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1answer
2k views

How to autostart a background program by a non-root user?

As a non-root user, I want to run a background job when the system boots. It's sort of a service which doesn't require root privilege. Is there a way to do it? One way is to put sudo -u user command ...
3
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1answer
223 views

Executing 'ssh-add -D' from a cron job doesn't work

I've set up an openSSH server on an ubuntu-server machine, and I configured it to use public/private key (without password). I want to require both password and key check when the client connects to ...
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0answers
27 views

Script executed from cron doesn't display GUI notifications [duplicate]

The script below has the name notifyrssh.sh. 1: File=/home/vaios/Desktop/tempcron/liveusers.txt //OK 2: cd /home/vaios/Desktop/tempcron 3: ps -aux | grep sshd > ...
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0answers
129 views

Scheduling cronjobs at specified time

I have scheduled some jobs in crontab which are to be run one by one, at some specific time. My script for crontab is : 15 10 * * * /Users/sri/files/BatchFF.sh 45 11 * * * /Users/sri/files/BatchGC.sh ...
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5answers
8k views

Run a script via cron every other week

I've done quite a bit of research in how to do this, and I see there's no direct way in cron to run a job, say, every other Thursday. Right now, I'm leaning toward making a script that will just run ...
2
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2answers
6k views

Run a sudo (or startup) python script from cron on a Raspberry Pi?

I'm helping out with an art project (http://stargateeggbeater.com/ for those interested) built on Raspberry Pi. The RPi controls an addressable LED strip through the GPIO, using the spidev device per ...
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1answer
204 views

How can I create cron jobs in specific files?

I want to have a separate folders for cron jobs like: /mydata/cronjobs Now in that folder I want to have files like backup_server which will have the content like: 30 3 * * 1-5 ...
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1answer
388 views

Deadlock in a crontab between cron and its child defunct processes

I'm having a strange case of deadlock, where the two processes launched by cron are defunct, but cron does not pick the return code and exit. I don't have access to the root user. myuser@myserver:~) ...
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2answers
2k views

Cron jobs and mail notification

I have (from one tutorial) cron job which make weekly backup on my website and is working fine. #!/bin/bash NOW=$(date +"%Y-%m-%d-%H%M") FILE="mysite.com.$NOW.tar" BACKUP_DIR="/home/user/backups/" ...
3
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2answers
259 views

Cron job for every minute executing out of order?

I'm setting up some shell scripting to be executed every five minutes, then every minute on our client's system, to poll a log and pull some timing information to be stored and accessed by another ...
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1answer
200 views

Creating Cron Task to kill stalled/failed runs in a system

I was given a task to create a cron which finds, kills and clears old puppet runs that were not successfully installed. I am more or less looking for a starting point.
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1answer
119 views

Cron job doesn't seem to be executing in ubuntu

I have a script located /myscript/script.sh and I have a cronjob that I submitted like this: sudo crontab -e The contents of the crontab are as follows: */1 * * * * ./myscript/script.sh The ...
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1answer
777 views

Why do I get different outputs when running my shellscript manually from when I run it with cron? [duplicate]

I have a fairly simple shell script (foo.sh) that looks like this: #!/bin/bash echo -n "$USER,$(date)," `binary -flags | sed -e '1,30d'`; exit 0; This script is supposed to prepare some output ...
3
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1answer
400 views

Cron job results are different from executing from own shell

I am using Ubuntu 12.0.4 I have a script basically with the following codes: lockfile=/var/tmp/mylock if ( set -o noclobber; echo "$$" > "$lockfile") 2> /dev/null; then exit_normally ...
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2answers
360 views

Linux 'mail' command: Can't open display

I've just installed the 'mail' command in Ubuntu (mailutils package) in order to view feedback from cron jobs. I type 'mail' at the prompt and see something like this: "/var/mail/*$USER*": 1 message ...
0
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2answers
4k views

Cron job not running / not successful?

I have a couple of cron jobs set up to maintain a local copy of a remote database. The first one downloads the latest version of the database from the remote machine, which runs every day and is ...
2
votes
1answer
376 views

Rsync over Rsync via cronjob

I have a local server which Rsync's from some computers on the LAN. It's a part of a backup solution. This Rsync runs via cronjob twice a day. Occationally people add gigantic amounts of data, like a ...
3
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1answer
645 views

ls gives me different sort orders during a cron job

I have a cron job that, among other things, does a recursive ls of a directory into a file. This gets compared to another file that I've created that, supposedly, contains an identical listing of the ...
4
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1answer
2k views

start-stop-daemon makes cron pidfile with wrong pid

I have an init.d script to start crond which specifies the following for start(): start-stop-daemon -S --quiet --make-pidfile --pidfile /var/run/crond.pid --background --exec /usr/sbin/crond ...
2
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2answers
3k views

Running `screen` through a @reboot cron job

I want to have a script running in screen at startup. This doesn't work: @reboot pi screen -d -m /home/pi/db_update.py however running this manually as user pi works: screen -d -m ...
3
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2answers
861 views

Automatic Update Script using Cron, Exit Codes, and Logging

I'm managing multiple machines running Debian, Raspian, and Mint. On some of the machines I want to have updating and upgrading automatically. I've drafted a script that I want to do this and log if ...
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3answers
4k views

How to run a shell script with export command in crontab

I have a shell script that exports values of variables when executed. The same values will be used in another script. How to run this script(test.sh) in cron. #!/bin/sh export I="10" echo $I I will ...
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1answer
223 views

How to prevent the termination of Anacron jobs after battery mode commences?

I have a backup script which is run daily by Anacron. It can take around 3 hours to complete. I'm happy for Anacron not to commence the script if the laptop is running on batteries, but once started, ...