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

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34 views

Need to automate the updating of the crontab file

We have an automated process where a server is built, and after applications/middleware are installed using another automated process, and the crontab needs to be updated for those ...
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2answers
75 views

Do spaces matter in a crontab

It's not clear to be from the manpage for crontab. IS extra white space allowed between the fields? e.g., if I have this: 1 7 * * * /scripts/foo 5 17 * * 6 /script/bar 31 6 * * 0 /scripts/bofh is ...
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1answer
49 views

High precision scheduler daemon

I'm looking for a scheduler daemon like cron, but with at least seconds precision so I can use it for a radio automation app. I've heard conflicting rumors about cron's ability to handle seconds. If ...
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1answer
62 views

Why can I not source a file with the default cron installed on a debian wheezy server? [closed]

I use cron for years now. In order to load all my environment variables at once, I define them in a dedicated file (often but not always .bashrc) that I source in the crontab: * * * * * (. ...
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3answers
1k views

Cron to not run on specific day but all other days

I have a cron setup to execute a bash script daily at 10pm. I have another cron setup to run monthly on the 1st of the month. Both crons launch a bash script, and the only different in the bash script ...
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2answers
2k views

How can I check if my cronjob is runnning on my server via PHP?

I would like to give out a warning If cron is not running or if a certain cronjob is not set in crontab on my server. Is this possible to check with php?
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1answer
124 views

How do I do “Hello World” to try using cron

I am using Fedora 20, and want, eventually, to set up automatic backups. I managed a trial run on my previous Fedora 12 installation, but can't get started again. I am using zshell. I thought I would ...
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2answers
313 views

How to make my bash script be able to create an log file for a clamscan running in cron?

I've created an custom clamscan(clamav) in bash and when I run it in my shell everyhing is fine, but if I run it in a cron, it can't create the log file. This are the errors: ...
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31 views

Why is there an apt-get script set in my cron.daily, I'm on Fedora 20?

I found this file tonight: /etc/cron.daily/apt.cron #!/bin/sh [ ! -f /var/lock/subsys/apt ] && exit 0 [ -f /etc/sysconfig/apt ] && . /etc/sysconfig/apt [ $CHECK_ONLY == "yes" ] ...
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3answers
2k views

set up local mail delivery to user from cron script

A line in my cron.daily script not work as expected. I haven't any special smtp mail server in system, this line rsync -avun --inplace /oneuser/file.xls /otheruser/file.xls| mail -s "$0 $?" ...
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1answer
7k 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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218 views

openSuse, not running the cron job

I have created a cron job in the /etc/cron.d/dispatchingEmail_I the permissions of dispatchingEmail_I are the following: -rw-r--r-- 1 root root 84 Sep 11 19:52 dispatchingEmail_I content of ...
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3answers
614 views

Using nohup to keep a script running indefinitely

I am very new to Linux and I've only been using it to SSH to my web server using Putty. The issue I am having is this: Basically I've got 2 php scripts. One get_tweets.php constantly listens for ...
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1answer
165 views

Unable to install crontab on OpenSuse

I am running the following command as root, on OpenSuse: linux-gn77-PC:/home/harbir/project # crontab -e when the editor opens up I type the following, as I want the command to be run at 2145 hours ...
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81 views

Execute All Cronjobs in ~/.zshenv Environment

I want to execute all cronjobs in the environment defined in my ~/.zshenv, and I want to redirect STDOUT and STDERR of every cronjob to a single log file. I am on OS X 10.9. What is the cleanest way ...
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1answer
34 views

Send cron mails to root bundled every hour

Sometimes when there's a problem on my server, I get hundreds of emails in my root account which are caused by cron. I want to be notified about those problems but isn't there a way to bundle those ...
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25k views

crontab's @reboot only works for root?

man 5 crontab is pretty clear on how to use crontab to run a script on boot: These special time specification "nicknames" are supported, which replace the 5 initial time and date fields, and ...
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1answer
24 views

Incorrect cron for midnight?

I checked the crontab set by the hosting company and they have this: 0 * * * * /usr/bin/php /www/sites/[domain.com]/files/html/shell/indexer.php reindexall Does this cron run constantly or once at ...
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5answers
4k views

Check if script is started by cron, rather than invoked manually

Is there any variable that cron set when it's running a program ? If the script is running by cron, I'll skip some parts; otherwise invoke those parts. How can I know if the bash script is started by ...
2
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1answer
71 views

Qt program not invoked by cron

I had a simple Qt program, when running, it shows a simple window with a countdown timer. If you might be interested in the code, please see here. I had crontab line * * * * * ...
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1answer
60 views

How to create CronJob for running commands on reboot?

Via my host I have SSH access and a control panel. I installed Rails via SSH on a light weight server. I want to reboot the server when it goes down. I think I need to start it manually since I want ...
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1answer
223 views

Run screen command with variable & tick through cron (cron run .sh)

I run screen command through cron, where the codes is in lorem.sh files. This is cron codes: * * * * * cd /home/z; ./lorem.sh Inside lorem.sh: screen -S screenname -X stuff $'\033[B' sleep 1 ...
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1answer
184 views

How can I periodically check if my network is up and reconnect if not?

I've written a script to periodically check whether my network is up by pinging three major sites and disconnecting and then reconnecting my network if all three fail. This script works fine from the ...
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1answer
105 views

crontab entry for a command to run every week and three months?

What would be my crontab entry for a command which I want to run every week. I don't want to run any command between 8 PM till 5 AM and any random day is fine. Similarly what would be my crontab ...
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2answers
353 views

Can I configure error notifications on a specific cronjob entry to go to a different email address?

I have multiple cron job entries configured under a single account: 0 0 * * * /foo/foo.sh 0 2 * * * /foo/foo2.sh 0 4 * * * /foo/foo3.sh Right now, if any of these encounter an error, an email is ...
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0answers
28 views

How to prevent cron emailing on termination

Whenever one of my cron scripts finishes, I get an email saying /bin/bash: line 1: 19653 Terminated <command>. How do I prevent this email being sent? I suspect it might only happen when the ...
2
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1answer
94 views

Running services without sudo

I want to run a nodeJS web server on a couple of machines which I don't have sudo access on. What would be a good way to do this? The two requirements are: running the service without being ...
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2answers
108 views

confuse about User:Group what is the best for /var/www, and Crontab user?

I'm new on linux server. I have 2 question that I'm confuse about this. 1 1. user:group now I chown my /var/www/html like this. my nginx.conf is set server{ user www-data } and in terminal I set ...
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1answer
242 views

How can I pass a filename containing percent signs (%) as a parameter to a shell script in cron? [duplicate]

We have currently setup a cron job for our new script as below: 46 22 * * * /gzm_common/diagbat9/global/prod/chgstatus.sh /backups/diagbat9/Demantra/output/SK_ITEM_EXTRACT_MFGPRO_$(date +%m%d%y).txt ...
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2answers
4k views

crontab error with (No MTA installed) but I use >/dev/null 2>&1

I'm new on linux user I try to run crontab to backup my database with vagrant user * * * * * /usr/bin/mysqldump -h localhost -u root -p root mydb | gzip > /var/backup/all/database_`date ...
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137 views

How to set cron job for system

I'm really new on Linux and have no any previous experience on it. And I opened this account to ask this question. I need to install a cron job I've followed the short guide here. Well, I think it ...
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3answers
15k views

Manually run a cron job / simulate running cron job?

I am new to cron and I want to test if cron's mailing stuff after an executed task and things like that work. Is there a more elegant way to test this, then setting a cron job to run every few ...
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1answer
494 views

Reboot when no network connection does not work!

I have a Raspberry Pi that I use as a NAS for my local network. It works fine, but when I turn off the router to which the pi is connected, it permanently loses the connection. To be able to connect ...
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211 views

systemctl to start cron-like job

In /etc/systemd/system directory I have: rsnapshot-backup.service file, with following content: [Unit] Description=rsnapshot backup automation [cron like] [Service] Nice=19 IOSchedulingClass=2 ...
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2answers
8k views

cron ignores variables defined in “.bashrc” and “.bash_profile”

I have defined "SHELL" variable in /etc/crontab file: [martin@martin ~]$ grep SHELL /etc/crontab SHELL=/usr/local/bin/bash [martin@martin ~]$ file /usr/local/bin/bash /usr/local/bin/bash: ELF 32-bit ...
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1answer
151 views

How to start a cron task?

It sounds really simple, but many times I was stuck at the beginning of learning a new command. The tutorial writer think it's natural to start, but it's not. This is the tutorial I've been reading: ...
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3answers
1k views

How can I start a cronjob 1 hour later each day?

I need to start a cronjob every day, but an hour later each day. What I have so far works for the most part, except for 1 day of the year: 0 0 * * * sleep $((3600 * (10#$(date +\%j) \% 24))) ...
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1answer
192 views

What should be the security context of these cron files?

I am running Fedora 20 and I am having some issues when running logrotate and anacron which I suspect may be related to SELinux: Failed to determine timestamp: Cannot assign requested address chgrp: ...
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1answer
650 views

Restarting process via cron every 12 hours

I'm not familiar with cron at all, and I've looked it up and am still confused as to how specifically it works. I'm on CentOS 6.5, and I need to end a process and then start it again every 12 hours. ...
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2answers
346 views

Backup of svn repository and mysql database on daily basis

How do I instruct Ubuntu 13.10 server to: zip svn repository dump mysql database into .sql script tar both files copy backup tar onto sdb disk Are there any premade tools for such kind of ...
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4answers
2k views

Anacron job complains “Gtk-WARNING **: cannot open display”

I'm trying to make a simple weekly Anacron job that backs up my computer if I click yes on the dialog. The script I wrote works fine if run manually, but when Anacron runs it, nothing happens and I ...
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1answer
98 views

Lock a script starting daemons

I'm run a script with cron: */10 * * * * flock -n /tmp/lock script I have to make sure that only one instance of the script is running at the same time, and for that I'm using flock. The problem is ...
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2answers
2k views

Sending cron output to email?

I'm trying to send cron output to an email address and am struggling... I'm running the following command: 13 15 * * 1-5 root /path/to/mysql-backup.sh 2>&1 | mail -s "Daily Database Backup ...
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2answers
66 views

`cron` service and `at` command

Help to understand: is there any relation between cron and at command. Actually if I stop the cron services in SUSE by running following command: /etc/init.d/cron stop after above, if I run at ...
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2answers
111 views

Create new temporary directory

What's an effective way of creating a new /tmp directory, that behaves just like /tmp (purged on reboot, etc.), but in a different location? In my case, I want to create a ~/dev/tmp directory where I ...
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2answers
4k views

How to kill a process in shell script which is running through cron?

I have a shell script which runs in cronjob. This shell script has to kill a process which is running and start the new process again. When I run the script manually it works perfectly fine, but when ...
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1answer
41 views

Run job at boot and on a schedule from same crontab

I have a process that I need to run on boot and periodically. I've created a file for it in /etc/cron.d/. Is there a way for me to specify that I want @reboot 0,30 * * * *?
4
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2answers
558 views

Schedule job at irregular intervals

It's simple enough to use cron to schedule a job to occur periodically. I'd like to have something occur less regularly -- say, run the job, then wait 2 to 12 hours before trying again. (Any ...
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0answers
28 views

How to find out why my cron didn't run? [duplicate]

This is the content of root's crontab: 0 23 * * 0-4 /usr/sbin/rtcwake -time `date --date="+16 hours" +"%s"` -m mem This is set to fire off that command every Sun-Thu at ...
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1answer
2k views

bash script not being run by cron [duplicate]

I have a very simple bash script that runs flawlessly when I do ./removeOldBackup.sh or sh /home/myusername/backup/removeOldBackup.sh but when I add it to crontab like * * * * * sh ...