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.

learn more… | top users | synonyms (2)

0
votes
1answer
348 views

Shellscript creating directories in wrong direcroy when running from crontab

I have written the following code which will create directories with name format "nowt_hour_minute_second". In that directory another text file will be created with the directory creation time. Now I ...
0
votes
1answer
914 views

Launch url to start a script like a cronjob?

I have a website on mutualised hosting (server A). I need to run every minutes a script, I just need to go to http//www.mysiteserverA.com/run.php I searsch a solution automaticly run this script every ...
2
votes
1answer
5k views

What schedules logrotate?

I'm working on the program which creates a big log file. I want to handle it with logrotate. This is a configuration I put to /etc/logrotate.d/: /var/log/myproject.log { hourly maxsize 1 rotate ...
1
vote
3answers
9k views

Root crontab not running

For some reason, my root cron tab does not seem to be running. Trying to reboot device every night at midnight. Should be the following as root: crontab -e Then add: 0 0 * * * /sbin/shutdown -r ...
0
votes
1answer
108 views

Custom cron job filename for a package

I'm willing to create a cron job for a package but when I define it in debian/cron.d it gets installed as /etc/cron.d/package. I'd prefer to be able to change the name of the cron job to be something ...
2
votes
1answer
669 views

This anacron cron job is sending emails to me - how can I redirect the output to null? [duplicate]

$ cat update-notifier-common #!/bin/sh set -e [ -x /usr/lib/update-notifier/package-data-downloader ] || exit 0 # Try to rerun any package data downloads that failed at package install time. /usr/...
1
vote
1answer
141 views

How to implement in upstart that a service is preventive restarted every x hours?

I have a component --- started with upstart --- with a bug. The bug causes the application to freeze and unfortunately, it does not crush. As a temporary walk-around, I want to force the service to ...
0
votes
1answer
99 views

run a script and return system to suspended or running mode

Somehow I cannot find how to do this common task. I want to run a (backup) script daily at certain time regardless whether the system is running or suspended and return to the previous state ...
0
votes
1answer
61 views

Why am I getting this annoying log messages.CRON[17405]: (root) CMD every minute

I have configured rsyslog.conf file to store log messages to mysql but I am getting some annoying log message in my MySql table. which looks like this. Nov 3 14:48:01 username CRON[17405]: (root) ...
0
votes
2answers
369 views

Crontab unable to open google chrome

I have written a chrome extension that performs a task whenever it is available, and for that I would need the chrome browser open at all times. My idea was to have a check say every minute if the ...
1
vote
1answer
53 views

CronJob not working as expected

I generated a cronjob line for crontab -e with Crontab Generator: * */2 * * * curl http://www.example.com/cron.php >/dev/null 2>&1 I was expecting that it should run every 2 hours. But in ...
1
vote
1answer
128 views

Cron process sends email, where are these sent emails?

Ubuntu 14.04 I have an email process that sends an email via cron, using sendemail (which I believe is a Perl program that doesn't need an MTA). Where are these sent-emails stored? If they are stored ...
-1
votes
1answer
263 views

Launch a .desktop file from boot

I have a .desktop file on my desktop that launches a html page. I need the .desktop file to run from startup, what would be the best way to do this? I have tried crontab and also the startup ...
0
votes
1answer
101 views

Cron emails no longer going to local 'chuck' account

Ubuntu 14.04 installed as a VM on a machine that sends emails, with attachments, via Perl 5.18.2. That part works because Perl talks directly to the SMTP server. Let's call the machine name "myubuntu"...
1
vote
0answers
28 views

Reading Cronjob Output [duplicate]

I have a task setup to run on my cronjob where I need to read the output. What I need from the output is the starting character (let's say A) and the ending character (let's say Z). A helps me ...
3
votes
2answers
344 views

Performance loss after 30 minutes

This one's baffled me. I have Ubuntu 14.04, 3 days ago (2014-20-10) it started slowing down. I've reproduced it by opening gedit and then closing gedit, when the issue is active it hits roughly 2 ...
2
votes
2answers
10k views

Cannot run bash script from crontab when it works from command line bash

I have a strange problem of being to able to run a bash script from commandline but not from the crontab entry for root. I am running Ubuntu 12.04. * * * * 1-5 root /home/xxxxxx/jmeter/...
0
votes
1answer
575 views

shutdown 5:30pm every day

for a five thirty pm shutdown, should I change this: 30 02 * * * /sbin/shutdown -h now to: 30 17 * * * /sbin/shutdown -h now see also: Crontab Shut down command didn't work
0
votes
2answers
560 views

How to create a cron job to monitor the status of a port ?

I am trying to create a cron job that would allow me to monitor the status of a particular port and send out notification via email while it changes from listening state to anything else.
8
votes
3answers
22k views

How to make crontab email me with output?

How can I make crontab email me with the output of its jobs? I have MAILTO=redacted@yahoo.com.au above the jobs, but it doesn't work. I know I need to use something like Postfix or Sendmail but for ...
0
votes
3answers
639 views

Run rkhunter regularely on a desktop system

I want to get a warning on my desktop when rkhunter finds something odd on my system. I whitelisted some files and dirs that seem ok in /etc/rkhunter.conf so I get no warnings anymore. Now I want to ...
0
votes
1answer
473 views

git push script, only if difference

I've found some nice questions illustrating how one would write a script automating git push/pull with cron here and here, but I want to elaborate on that slightly. I only want to push/pull if there ...
2
votes
2answers
285 views

Cron Job Creation

Okay, so I have had a quick look at the answers posted on this question and re-formulated my cron job. So, let me break this down as clear as I am able to: PC/OS | Shell Info I am currently running ...
1
vote
1answer
360 views

Question about CRON trim weekly

I have got samsung SSD and so TRIM is on automatically. However I am bit confusing about how TRIM cron weekly starts. According to cat /etc/crontab it says that CRON weekly will start at 6:47am (odd ...
2
votes
1answer
736 views

How do I change my cron loglevel to 7 from default value 1?

> man cron, tells me that the default log level for cron is 1; i.e. cron "will log the start of all cron jobs." I want to set that to 7, so I checked in all the wrong places, starting with the file ...
0
votes
1answer
224 views

Cron job daily not running

I'm having trouble with setting a cron job to run daily when I enter the script to /etc/cron.daily when I put it there it doesn't run at all like it should be doing. I setup a script so that it can ...
2
votes
1answer
329 views

Running Chrome extension periodically using a cronjob

I have built a chrome extension that performs a set of actions on a random webpage. The extension seems to work fine and I plan to run it on a VPS running Ubuntu with a XFCE desktop environment. Now ...
3
votes
1answer
190 views

How can I start a shutdown with cron,only if no download is in progress?

I would like to shutdown my computer half-past twelve every day and can do that with "echo "30 0 * * * /sbin/shutdown -h now" > myrootcron.sh",but what if I want to cancel that shutdown or leave it ...
4
votes
3answers
501 views

Cron jobs are disabled on clean installation of 14.04

I have a clean installation of Ubuntu 14.04 and in my /etc/cron.daily/ I see *.disabled files: -rwxr-xr-x 1 root root 15481 Apr 10 09:04 apt.disabled -rwxr-xr-x 1 root root 314 Feb 17 2014 ...
3
votes
2answers
2k views

Ubuntu 14.04 and playing songs from cron

I recently upgraded my computer to Ubuntu 14.04. After the upgrade the system no longer plays the few songs I had it play via crontab. The crontab lines look like so: 0 9 * * 1-5 /usr/...
0
votes
1answer
248 views

Problems with MAILTO setting: server doesn't sent cron's e-mail

I have Ubuntu 14.04 with Postfix mail server. Php/apache can send e-mails. But i don't resive any messadge from cron. Here my setup: MAILTO=crantisz@gmail.com */2 * * * * wget -o /home/user/out.html ...
1
vote
1answer
345 views

Change system volume using crontab & pactl

I am trying to change Ubuntu 14.04 system volume using crontab. I am using following command: pactl set-sink-volume 1 75% Which works fine when I use it in terminal or when I run script which ...
1
vote
1answer
4k views

What is the default timeout value for curl when used as command on terminal?

have searched a lot to find out default timeout value of curl. All suggests how to set timeout limit for curl. But Can anybody please suggest what is the default value of curl command timeout time? If ...
0
votes
1answer
56 views

running a tar command eats all resources

I am running a Rails application on my ubuntu 12.04 server. I have set up a cron job to take backup of all files uploaded to my application every morning at 2 am. It is a lot of files (around 900 mb). ...
0
votes
1answer
974 views

Alternatives to Cron

I'm doing a server running Ubuntu Server 12.04 and Apache. The users have continuous updates in the dinamic pages through a Java script, downloading JSON files through Ajax request to server. All the ...
1
vote
1answer
2k views

Crontab not executing jobs Ubuntu 14.04

I am trying to run bash script as a cron job every 15 minutes. The bash script simple calls a Java program. I made an entry in crontab to run the file every 15 minutes and saved it but it would not ...
1
vote
3answers
663 views

Not able to run sed on bash script

I am working trough some legacy code which does not work, I came across a part that is causing problems. I was hoping some one could help me out and fill me in on what is the exact functionality of ...
1
vote
2answers
426 views

Schedule a large download to resume everyday in a specific time-span of the day?

I want to schedule a large download to occur at night, between 12AM and 5AM. Everyday at 12AM wget should automatically pick up where it left the night before, and at 5AM, it should automatically ...
1
vote
2answers
1k views

can't reattach to screen

I've been having problems with screen (the terminal command). If I type screen -ls it gives me: No Sockets found in /var/run/screen/S-root. For screen -r I get: There is no screen to be ...
1
vote
1answer
518 views

Crontab not executing script with cURL

I have a cron that's set to run every ten minutes that works fine if I execute the file manually by entering php register.php But, my cron will not execute this file once it includes anything cURL ...
2
votes
0answers
174 views

Cron, xconf-query and Xubuntu 14.04

I have updated my Xubuntu to the 14.04 version. Unfortunately, I am experiencing a problem. I have a script, named earth, updating the wallpaper of my desktop. Here is the code #!/bin/sh nice -n 19 /...
10
votes
3answers
13k views

Why is this rsync + ssh cron job giving me 'Permission denied (publickey)' errors?

I make frequent backups to a local drive which I want to sync daily to a remote server. The target server is configured for SSH key (no password) access only. Since my primary SSH key for that server ...
0
votes
1answer
332 views

Is there a programmable way to tell if the screen is locked with the new Unity interface?

I have lots of stuff in my crontab, including some that talks to my screen. If I'm not there for it to be notifying, I don't really want it to run. Is there a way I can check to see if the computer ...
1
vote
1answer
4k views

Who runs scripts inside /etc/cron.hourly if anacron is enabled?

I've read that if anacron is enabled cron doesn't run the scripts inside cron.weekly/hourly/daily/hourly, as not to run them twice. So anacron takes responsability on that folders. However anacron ...
6
votes
1answer
952 views

unattended-upgrades error: “/etc/cron.daily/apt: DB Update failed, database locked”

Ubuntu 14.04.1 LTS Since installing unattended-upgrades, the following error message is received daily: From root@xxxxx Thu Aug 28 06:36:06 2014 X-Original-To: root From: root@xxxxx (Cron Daemon) ...
0
votes
2answers
76 views

Crontab command does not function properly

I have the following crontab entry to automate copying of my files to separate W/S in the network. However, it does not copy the files but produce the log file. here is the file contents #! /bin/...
8
votes
2answers
3k views

How to start a GUI application from cron?

I need to run a Java applet from a Firefox. The problem is, I need to run this Firefox from a cron. If I run from the command line and its work fine, but when put the command in the cron it failed: */...
-1
votes
1answer
695 views

How To Run A Shell Script Again And Again Having X Interval Of Time In Root? [duplicate]

I have a shell script in my Ubuntu Server 14.04 LTS at ./ShellScript.sh. I setup /etc/rc.local to run the shell script after boot but before login using below code. To run run it boot write this ...
0
votes
1answer
533 views

Unable to execute expect script via cron even with the permissions set to 777

I created an expect script that won't seem to run when called by cron. I included the full path in cron when calling it as follows. * * * * * /usr/local/sbin/checkForRemoteTasks >/...
0
votes
1answer
274 views

Tell me where is mistake in anacron task?

I have tried to make this task for abacron: dm@dm-system:~$ cat /etc/anacrontab # /etc/anacrontab: configuration file for anacron # See anacron(8) and anacrontab(5) for details. SHELL=/bin/sh PATH=/...