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

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Pimp rsyslogd to have less i/o (cron, pam,…) and less logging

On my raspberry I really don't need crons and pam logging and I want to have less i/o to make the SD card life a little longer.. I have already removed cron with the second line cron.none, I'm ...
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2answers
73 views

RSync Error in script

At my job, we have a central Backup server, running Debian Wheezy, and on-site servers at each site, also running Debian Wheezy. A few weeks ago, the central office tech emailed me that the backup ...
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2answers
51 views

Run and stop a monitoring command as sudo for s seconds every m minutes

I want to run sudo airodump-ng -w myfile every ten minutes or so, for m minutes. It does not matter if the running time shifts (that it, if it runs m minutes later each time). Notice that this is a ...
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2answers
20 views

Cronjob based on system time or its own time elapse

Cronjob is based on the system time or its own time elapse? If it is system time, when I change the system time manually, will cronjob follow the new set up time accordingly?
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154 views

curl and wget cut off url

I have a web cms that allows so called action IDs which are urls. When you hit those, they perform some code in the cms. So I wanted to perform an action periodically and used cron for that. PROBLEM: ...
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3k views

Null message body; hope that's ok

I have the following command below as part of a cronjob. When I run the command via cron or at the command line, I get Null message body; hope that's ok. The contents of the email are empty but when ...
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14k views

How to use Crontab for a java file in linux

How can I use Crontab in Linux specifically for a Java program? I want to run a MIS Script. How can I crontab it and what should the path be?
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CentOS Crontab - Extract particular file name

Let's assume that I have a file with extension of .7z and I have a crontab that extracts this file. But the name is unknown, only the extension is known, is it possible to extract it from crontab? ...
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232 views

What user should I create and execute cron jobs as? Apache? Root? Me?

I'm setting up a new Webserver and having trouble getting cron to execute as expected. I am using a script to create cron jobs in .tmp/crontab.txt, which is then moved to /var/spool/cron under the ...
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2answers
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Why is mail-utils / cron sending out so many emails?

I was trying to troubleshoot why my Raspberry Pi isn't sending emails with ssmtp / mail-utils, and so I opened up my gmail account that I use for the Pi. To my surprise, there were 15k unread emails ...
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How can get a list of all scheduled cron jobs on my machine?

My sysadmin has set up a bunch of cron jobs on my machine. I'd like to know exactly what is scheduled for what time. How can I get that list?
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Is it possible to store user's crontab in user's git repository on OpenBSD?

On OpenBSD and with OpenBSD's cron and crontab, is it possible to store the crontab(5) of a user in a git repository of the same user? What would be the proper way to accomplish something like this? ...
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52 views

cron job with slash

I got a cron format like this: 0 0 12 1/1 * ? *, How to read it and what does it mean. I understand things without slash but not this one.
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23 views

Where is the users cronjob

i have build a cronjob for a single user www-data user by using sudo -u www-data crontab -e i'm trying to find where this file is saved, i have looking in /etc/crontab but its not here, soe i can't ...
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83 views

Perl script is running fine in interactive shell but not as a cron job

I have installed dirvish for some backups. I have initialized one vault (host). And now I am using the following script to run it: #!/bin/sh /sbin/dirvish-expire --quiet && ...
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62 views

What would crontab do if the server is shutdown?

Say I have a crontab like: */30 * * * * /root/scripts/remove_log_files.sh This will remove some logs that I don't want every 30 mins. What would happen if the server shutdown after 25 mins the ...
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355 views

Display cron job times in a human-friendly format

Is there a way to display or is there a tool that can parse a crontab expression and display it in a human-friendly way? 10 6 * * * sh /usr/local/crons/file_check.sh For example, for the above cron ...
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34 views

error while changing directory using crontab [closed]

This is my script I am trying to rename the files in folder. rename1.sh ---------- #!/bin/bash cd /home/lanein1/WestonIN7pm/"$(date +%Y-%m-%d)" && rename s/WestonIN/WestonIN7pm/ *.jpg cd ...
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Cron job runs more often than I thought it should

I have a cron job that is running twice an hour. It runs once at HH:00 and once at HH:45. This is strange because I tried to specify that it should run every 45 minutes as follows: */45 * * * * ...
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1answer
356 views

Pushing to a Git repo from shell script

I'm trying to commit/push changes to a remote Git server with the below sample code: #!/bin/sh USER='username' REPO='/home/'${USER}'/Sites/git/bitbucket/kb' COMMIT_TIMESTAMP=`date +'%Y-%m-%d ...
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1answer
49 views

How to show Java dialog when cron runs the Java program?

I've done a little java program that ends showing a dialog after doing some other tasks like reading from a web and writting on a file. My goal is to make it run everytime my system starts with 90 ...
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525 views

Correct capitalization of “cron”

I'm not quite sure what the standard is for spelling cron. Does one capitalize the whole word? Just the "C"? All lowercase? Is there even a standard, or do you just spell it in whatever way looks or ...
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36 views

Add cron to Crontab

I am looking at these tutorials https://www.digitalocean.com/community/tutorials/how-to-use-cron-to-automate-tasks-on-a-vps and I have cron installed but when I write the command 5 * * * * curl ...
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Cron job to delete files older than 3 days

I need to remove files older than 3 days with a cron job in 3 different directories. (these 3 directories are children of a parent directory /a/b/c/1 & /a/b/c/2 & /a/b/c/3) Can this be done ...
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549 views

systemd - Timer units that mimic anacron behaviour

I need to write a timer unit for a machine which is turned of frequently (e.g. classical desktop setup). This timer unit needs to be activated regularly but not very often (e.g. weekly, monthly). I ...
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Installing crontab using bash script

I have created a script to install two scripts on to the crontab. #!/bin/bash sudo crontab -l > mycron #echo new cron into cron file echo "*/05 * * * * bash ...
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Run Script once a day with systemd

I want to run a backup script 10 minutes after booting up my machine but only once a day. Is it possible to build up such scenarios with systemd?
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1answer
2k views

how to temporarily disable a user's cronjobs?

How do I temporarily disable one or more users' cron jobs? In particular, I do not want to suspend the user's cron rights - merely not fire any of their jobs. I am on SLES 11 SP2 and SP3 systems
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2answers
177 views

Cron only occasionally sends e-mail on output and errors

On Debian 8.1, I'm using a Bash feature to detect whether the stackoverflow.com website is reachable: (echo >/dev/tcp/stackoverflow.com/80) &>/dev/null || echo "stackoverflow unreachable" This is ...
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47 views

Cronjob and Mapcrafter for Minecraft not running the renderer

I am using two Raspberry Pi 2 computers: one to run a Minecraft Server, one to run Mapcrafter (http://mapcrafter.org/index) to setup and update the server's map on my Apache2 server. I am using cron ...
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1answer
7k views

mail: cannot send message: process exited with a non-zero status

I've had a cronjob working for about a fortnight without any problems. Then last night I checked I didn't get the email that I usually get. I went to the terminal to try send myself an email, I got ...
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Crontab job start +1 min after @reboot

Need a script executed at each reboot in +1 minute. I placed a record @reboot but it is too early for my script. How to execute it sometime after reboot?
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running cron on a chroot

For my web development I use a debootstrap'ped Debian with sysvinit, I start apache2/mysql manually only when I need to work. Now for a new project I require to run some scheduled task for which I ...
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175 views

Script won't run in cron but runs fine in root shell

My Problem: I have a python script that runs fine when run manually but does not complete when run using cron. My script fails in cron because it contains pexpect commands that require an interactive ...
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2answers
1k views

Can grep | crontab destroy all jobs?

My colleague ran grep | crontab. After that all jobs disappeared. Looks like he was trying to run crontab -l. So what happened after running the command grep | crontab? Can anyone explain?
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I cannot kill crond - trying to stop cron service

This is frustrating, I try: service crond status And get this: Redirecting to /bin/systemctl status crond.service crond.service - Command Scheduler Loaded: loaded ...
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Why a crond can start late randomly

I have this issue of a cron that executes a PHP script at minute 20 every hour, This script generates a small number of reports based on data from a MySql database. Generally this script ends ...
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404 views

Script with curl works manually but not in cron job

My script (status.sh) is: #!/bin/bash SITE=http://www.example.org/ STATUS=$(/usr/bin/curl -s -o /dev/null -I -w "%{http_code}" $SITE) if [ $STATUS -eq 200 ] then echo $STATUS >> ...
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Prevent ssh-keyscan from generating output

Problem: When running ssh-keyscan in cron it emails me the output of ssh-keyscan every day. The email simply contains the following. # <hostname> SSH-2.0-OpenSSH_5.3 My (simplified) cron ...
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288 views

Why does OpenSSL automatically send me Terminal mail?

I for some reason am getting messages from OpenSSL constantly (not literally constantly, but every hour or so) sent to my Terminal mail box saying: Message 1: Subject: Cron ...
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1answer
39 views

Have cron check if the bash script is executing

I have a bash script that users while do along with sleep to constantly monitor the connection state and take measures in case something goes wrong. The only thing that is not guarded is the execution ...
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1answer
57 views

Does rsync over any type of checksum? [duplicate]

I need to transfer files from several servers to a single remote host using Rsync over SSH. However, I need to be sure that before the file is deleted on the source using the --remove-from-source ...
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1answer
52 views

crontab versus manual running script

I wrote a script to check for wifi connection that has an "if then else" statement. If I run the script manually the "if" statement is 1, as it should, if the crontab runs it automatically the "if" is ...
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1answer
546 views

How to make OpenVPN to autoreconnect to gateway at any time

I've recently discovered a built-in way to have OpenVPN to auto connect to VPN gateway on startup, which is via setting profiles .conf files in /etc/default/openvpn as a part of AUTOSTART parameter. ...
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36 views

Simple bash not running properly by cron

I created a small bash script that takes a file using wget and then processes it using a php. The code goes like this: wget -U mozilla -P /home/logfetcher/ http://fakesite.com/log.`date -d ...
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Stop cron sending mail for backup script?

I have set up a backup script to back up world data on my Minecraft server hourly using cron, but because the worlds being constantly edited by players, tar was telling me that files changed while ...
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How to override email address used by at command

cron has MAILTO setting to explicitly configure the email address that will receive the report Does at have anything of the kind? Man page says it will send using /usr/sbin/sendmail but which ...
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Cronjob is running every minute but not at a specific time

As title says the job works if set like this: */1 * * * * /usr/bin/php /home/test/cron/test.php And if set to something like: 15 20 * * * /usr/bin/php /home/test/cron/test.php it's not working. ...
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378 views

Shell Script does not send email from Cron job [duplicate]

I have a shell script which sends email when the disk is more than 80% full; when I run the script as sh -x script.sh or ./script.sh I get an email but when I keep the script in cronjob I do not get ...
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24 views

Move files that are 7 days or older, cronjob [duplicate]

I want to move some log files that are 7 days or older to another folder and then delete those files after another week. I'm using logrotate to create a new log file every 2 hours in a folder. I ...