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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Command with backticks and percentages not running in crontab

The following crontab does not work: # TEST LINE DOES DOT RUN */1 * * * * /bin/echo 'test '`/bin/date +%Y-%m-%d` >> /tmp/test I also tried starting it with: SHELL=/bin/bash Update: I ...
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477 views

What does this (root) CMD line in system.log mean? Why is it there?

What does it mean? (root) CMD ( [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin ...
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2answers
75 views

What does this mean in “crontab -e”?

When I run crontab -e, I see this bit: Notice that tasks will be started based on the cron's system daemon's notion of time and timezones. How to convert the cron's system daemon's notion of ...
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1answer
489 views

Script not running in crontab, file not found

I need your help to run a bash script in crontab. As many other posts in askubuntu I'm facing the problem that a script that is properly running in terminal mode does not run in crontab. The error I ...
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94 views

Deja-dup cannot access Truecrypt volume when run from Cron

I have a deja-dup set up to backup into a mounted Truecrypt volume. It works fine but now I would like to run deja-dup in my own intervals via Cron (set up for my account): * * * * * env DISPLAY=:0 ...
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417 views

Using a cronjob to clean /tmp

Is it save to use bash script and a cronjob to remove all files in /tmp? Or should I do this differently for other reasons, maybe?
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4k views

Cannot run cron job for a php script

I want to run a php script using cron job on localhost my script is situated at - /opt/lampp/htdocs/rrugd/myscript.php now as opt is under root, i tried adding the cron job for root as well as ...
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767 views

Ubuntu VPS Automatic Backup Script

Can anyone tell me how to create a backup script for Ubuntu VPS which is used as a webserver. I also want to add it as a cron job so that it runs automatically every day midnight at ...
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3k views

Create a Screen session with a bash script using contab

I want a .jar file to run every time the server boots up (we're using a VPS), and so I've edited crontab using crontab -e and then adding @reboot bash /home/bash/startserver.sh. But I haven't even ...
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1answer
51 views

Scheduled Power On/Off of 2nd HDD

im using a ubuntu 13.10 Server. I want to switch off the 2nd HDD completely and only power it up once a week to back up the system+data from the 1st HDD. I know how to use crontab, but I dont know how ...
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48 views

Crontab wont run a script

I've set a script to run every 10 minutes using cron, but it does not run. It works when I run it manually. bin path is /usr/bin/. The script contains: #!/bin/bash scrot 'screenshot.png' -e 'mv $f ...
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160 views

Start-up / Reboot scripts for different users

I'm still trying to learn a little more about bash scripting and start-up / reboot, I have read about crontab @reboot and also just looking at other options but I just wondered if someone could maybe ...
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54 views

# in crontab used for what?

If I add up the # in front of some crontab task then it won't work and behave as comment ? right ? I want to disable some task for sometime until I like to enable. # * * * * /home/user/xx Thanks ...
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1answer
191 views

Ubuntu Server cron job doesn't work

My script that is supposed to run only when the server is on isn't working correctly when run by cron. If I run it manually, it works. backup() { if pidof java &> /dev/null; then ...
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1answer
46 views

Check when folder was last synchronized with rsync

I'm using a cron job to backup a folder to another computer. I'm not sure whether or not it succeeded and /var/log/rsync.log is only showing errors, all of which occured before the scheduled backup. ...
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249 views

screen shot from command line

I am writing a sh file to take screen short and want to schedule in crontab but when i run the .sh file it run OK no problem happens but when try to schedule it in crontab i got an error like ...
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1answer
1k views

Crontab GUI for Ubuntu 12.04

Is there any app for the Ubuntu 12.04 LTS (server, no visual interface) in order to easily manage crontab? Maybe a daemon running in background and access to it via a web browser? Using crontab -e is ...
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2answers
7k views

Crontab error “No crontab for root”

when I write crontab -e command in terminal, I get this error message: no crontab for root - using an empty one 888 I don't know what '888' is meaning? Config file of crontab /etc/crontab: # ...
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4answers
20k views

How to Setup a root cron Job Properly

I tried to setup a root cron job to run a Bash script as root, to run at minute 7,37, every hour, every day of month, every month. This script is located in /usr/bin and named tunlrupdate.sh is used ...
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324 views

Cronjob for MySQL Backup Bash Script Not Running

I am trying to backup many MySQL Databases on a daily basis into a Single ZIP. The bash script works fine by itself (ran in normal environment), but when the Cronjob takes over it does not run. Infact ...
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569 views

How to detect error in cron jobs

The reasons why a cron job may fail is really very large. Most common reasons may be, Syntax error Using executable without proper path Using a shell variable which is not defined in cron ...
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54 views

Make CronTab not asking for id_rsa keyword when running in terminal

I like to do some git pull inside a script and see see output of it. So I made up this cronjob to test: DISPLAY=:0 * * * * * mike /usr/bin/gnome-terminal -x zsh -c "/var/www/up.sh; zsh" ...
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2answers
39 views

How to put availabe disk space into filename?

I have a SFTP user only and I want it to be able to see available space. I want to make a cron that runs each 30 minutes, to delete the old file and put the new file to show free disk space. I could ...
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1answer
3k views

Running PHP Cron Job with Arguments

Im trying to run a PHP script, once a day, on ubuntu 13.10 server with php5. I have cron jobs set up, via ajenti control panel, verified with crontab -l, for this command. php /path/script.php ...
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12k views

Open firefox from bash file “Error: no display specified”

I need to open a browser and access my server with the ip address 1.2.3.4. First I ping my server and if the ping did not fail I launch the home page in a browser. For this I have written a bash file ...
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93 views

Why the cron job did not fire on ubuntu 12.04?

Here is the script sqlite_backup.sh under $HOME/: #! /bin/bash now=$(date +%d) echo "Welcome to Sqlite backup script" sqlite3 /var/www/db/nbhydb.sqlite3 << EOF .timeout 20000 .backup ...
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2answers
53 views

Network Information for Theft Prevention [closed]

I haven't seen much of this around, and I'm not a network expert/sysadmin, so I need some advice. I have a laptop that I'd like to "protect" against theft (this is really a game more than a real ...
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1answer
280 views

System crontab entries not being run

I am running Ubuntu 12.04 LTS Desktop. I have used the /etc/crontab to set up a couple of entries that should run at different schedules. Now, the problem is that these do not seem to be running. I ...
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3k views

no crontab for [username] - using an empty one

I want to run a bash file (abc.sh) on the desktop that runs a python file on the desktop as well. How can I do that? I tried to do the following simple task just to test the crontab: (here the abc.sh ...
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5k views

How to remove or delete single cron job using linux command?

I have created cron jobs for my site which is listed below and they are working fine.I print all cron job by using this command $cronfiles=exec('crontab -l',$output); echo "<pre>"; ...
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175 views

Why do I get that error from a CRON job?

I am trying to write a cron script to check if my minecraft server is running or not and if it is down to run the start up script. Here is what I have and this is the error I get when running it ...
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60 views

Only part of crontab working [duplicate]

i have a line in crontab: * * * * * date >> /home/pana/temperatures.txt; hddtemp /dev/sda >> /home/pana/temperatures.txt ;hddtemp /dev/sdb >> /home/pana/temperatures.txt ;sensors ...
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Is it possible to limit Software Center or apt-get install downloading to a specific time of day?

I have free bandwidth everyday from 12 am till 7 am. That means I put everything that I want to download in the software center and go to sleep. I want the download process to stop at 7 am. For that ...
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1answer
72 views

cron not outputting correctly?

Please forgive my ignorance. I have searched, but perhaps I’m not sure really what to search for in order to answer my question myself, so I’m turning to this forum for a little guidance. I’ve ...
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137 views

Where to check if a cron job was ever run?

I set a few cron jobs locally on my machine. They were supposed to run each night at 8 PM. Where can I see or check that they actually run?
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79 views

A shell file containing count but not showing when I try to run from crontab

I am new in writing shell script i write a script like this #!/bin/bash PID=$(ps -ef | grep "sh gps.sh" | grep -v grep | awk '{print $2}') if [ -z $PID ] then cd /opt/etrans/cronjobs ...
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138 views

Configuring logrotate without root access (per user log rotation)

How best can logrotate be configured, on a per-user basis, to rotate files in the home directory of the user, under control of a per-user 'crontab -e'?
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2answers
1k views

Setting cron to run a shell script: random wallpaper from a webpage

I have written a shell script which downloads random wallpaper from a web-page and sets it as a background every 5 hours. Here is the script: #!/bin/bash countervar=1; finish=0; cd ...
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3answers
2k views

Who is sm-msp-queue and how does he/she/it flood my /var/log/syslog?

I run Linux BeagleBoard-xM 3.12.5-armv7-x10 #1 SMP Fri Dec 13 03:06:20 UTC 2013 armv7l armv7l armv7l GNU/Linux and my /var/log/syslog gets flooded by messages like Jan 11 10:21:09 BeagleBoard-xM ...
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535 views

How can I get mysqldump to use the credentials from mysql_config_editor in a crontab-executed script?

I am setting up a daily backup of a MySQL 5.6.14 database using mysqldump on an Ubuntu 12.04 Precise server. I created the credentials file in the root home directory (.mylogin.cnf) according to the ...
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73 views

Crontab script entry not working

beginner here. I have a script called updateTf2.sh It's contents #!/bin/bash /etc/init.d/srcds stop ./steamcmd/sh +login anonymous +force_install_dir ./tf2 +app_update 232250 +quit ...
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3answers
242 views

Can't get crontab to repeat command every five minutes

I'm trying to make crontab run a sh script every 5 minutes. This is my root (sudo crontab -e) crontab setup: */5 * * * * /etc/test.sh and this is the script: #!/bin/bash echo "time:$(date)" ...
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179 views

Running Key Remap Script at Startup

I'm trying to re-map my left Alt key to the Alt Gr and Alt Gr to Left Alt. So far I've been able to do it in terminal, but it never runs it on start up. I've read multiple AskUbuntu questions, but ...
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116 views

crontab entry to reboot than email

I got my weekly crontab reboot entry to work using /sbin/shutdown -r but now I want it to email me when the reboot happens. Ideally I would like the email to happen after it rebooted so I know the ...
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Folder Action for Ubuntu [duplicate]

I have a question concerning Ubuntu folder action , I need a script to notify me when a file is add to a folder or the folder changes , is there any possibility for that. I found some articles ...
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62 views

Cron Script Length

I have a backup script, a script that cyncs file with other files on my computer, and a script that uploads files to my website with ncftp. I used cron to load .sh files, and my shorter scripts work, ...
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Using a NAS as a collective dump, with symlinks for whoever uploaded each file

I have a local machine that was sitting around & doing very little, so I decided to turn it into a NAS (Network Attached Storage) machine, with a 40GB disk for Ubuntu (13.10), a 160GB disk that's ...
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392 views

how do I use upstart, instead of cron, to start a single instance of a job which should always respawn?

How do I script the following bitcoin/dogecoin/etc cpuminer command: /home/digger/cpuminer/minerd -o stratum+tcp://doge.pool.webxass.de:3333 -O <user>.<worker>:<worker_password> ...
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3k views

cron error: bad username

I've basically re-written the terminal output instead of appending a series of edits to this question: root@doge:/etc/cron.d# root@doge:/etc/cron.d# tail /var/log/syslog Dec 21 11:35:01 doge ...
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213 views

task scheduler in system settings does not appear

i install KDE's Task Scheduler to be able to access to crontab via GUI . After install , i try to open this soft , however , i cannot find where it is. I follow this DEMO on Youtube , and i note ...