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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165 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?
2
votes
1answer
17 views

Reset hibernation delay from command line

My hibernation on Ubuntu 14.04 LTS works fine. But someone keeps changing its delay to never hibernate. I am tired of paying days' worth of electricity for 10 minutes usage a day. Is there a way I ...
1
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1answer
23 views

Cron can't find file at night? [duplicate]

I have a cron job written to root (I'm writing to a log in /var/log so need root permission). The problem is that sometimes it works, and sometimes it doesn't. The cron job is simply to call a python ...
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0answers
12 views

How to keep cluster systems in sync

I am wanting my devices on my cluster which all have the exact same specs (Raspberry Pis) to completely be in permanent sync. I have been thinking of using a cron along with an rsync but I am not ...
0
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1answer
22 views

sleep getting hang in shell script

I had a cron script running on my Ubuntu PC ( 12.04.3 ) which periodically checks for disk space. There was a "sleep 5" also used in this script. This system was up for a month, but an issue is ...
3
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2answers
67 views

Why putting a script in /etc/cron.hourly is not working?

I put an executable script in /etc/cron.hourly, but that script didn't run every hour actually it never runs at all. Here is the script(Hour-sound) that i made: #!/bin/bash mplayer ...
3
votes
2answers
2k views

CRON is changing encoding?

I have a legacy Java program that outputs an SQL script. I then use Apache Derby to run that SQL on the target database (which is not on the same server as CRON). When run via putty, this works fine. ...
1
vote
1answer
20 views

log cron job in real time

I have a Python process which I run nightly via a crontab. It scrapes an API which I have limited access to so regularly has to stop and wait for an hour. By my estimates the job should take 5-6 ...
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2answers
3k views

How to add the logs to a crontab with time stamp

In crontab, I scheduled a daily backup script. Now when the cron executes the script the status are logged to a log file as shown below. 0 0 * * * /home/backup.sh > ...
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3answers
241 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 ...
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2answers
35 views

What is the correct way to edit a crontab file?

I am trying to automate the refreshing of awstats for my webserver and understand that i need to use cron to set that up. So each user has a crontab file? I was following the instructions here ...
6
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5answers
10k views

cron.daily jobs not running

I created 3 daily cron jobs to run. Below are the three that are placed in etc/cron.daily rkhunter.sh #!/bin/sh ( rkhunter --versioncheck rkhunter --update rkhunter --cronjob --report-warnings-only ...
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3answers
17k views

Use /etc/aliases for outgoing mail relayed by postfix with local domain

I'm using Ubuntu 12.04 with postfix configured as satellite system that relays outgoing mail to Gmail. For sake of example, my registered domain is example.com I want root cronjobs' error output to be ...
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vote
2answers
2k views

Auto shutdown server if there was no activity

My server should shutdown after 01:00 am, if there was no activity in the past hour. Lets say there was the last connection at 00:43 then it should check again at 01:43. How to write such a ...
2
votes
0answers
25 views

No crontab for user, yet cron jobs are running

I have no apparent crontab: $ contab -l no crontab for gauthier Yet, something seems to be running as my user: $ tail /var/log/syslog ... Apr 13 16:25:01 sobel CRON[22043]: (gauthier) CMD (rsync ...
2
votes
1answer
15 views

Time based access to samba server

I have a 14.04 server running samba. I'd like to institute some time based access to the server. I host media for the whole house, and the goal is for the kids' televisions to become useless at a ...
182
votes
33answers
269k views

Reasons why crontab does not work

Often, crontab scripts are not executed on schedule or as expected. There are numerous reasons for that: wrong crontab notation permissions problem environment variables This community wiki aims ...
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3answers
2k views

Function of /etc/cron.hourly

If I create a script and then place it in this folder (/etc/cron.hourly), will my system run this script hourly? Or does my script need to begin with a command as well?
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votes
1answer
14 views

different behavior of script when it runs on crontab

I'm trying to write a script that checks if mysql is running, and if not restart it... i get a script to run perfectly if is called manually from terminal, but when i added to crontab it outputs is ...
3
votes
3answers
4k views

Is there a way to suspend/sleep via bash?

I have to get nine 46" LCD monitors (running Windows) to suspend/sleep at 8pm and wake at 8am every morning. It's been a bit of a mess trying to get the commands working, including the privileges. ...
4
votes
1answer
35 views

Permanently raising nofile limits in Ubuntu 14.04 LTS

I cannot seem to figure out what exactly is needed to allow the maximum number of file descriptors to be raised permanently for all users. /etc/security/limits.conf: root hard nofile ...
3
votes
1answer
46 views

Create zip files in /var/www/html using crontabs

As the title explains, I'd need to take a file and put it into a zip archive once a day; also, the zip file has to be moved in /var/www/html, where a .php scripts allow users to download it. Assuming ...
1
vote
1answer
59 views

reprepro - Is there any chance to enter the passphrase via bash-script?

I use "reprepro" for getting the latest Debian packages out of my local repository, which works fine manually. Now I need to automate this process through a cron job but the reprepro passphrase is a ...
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0answers
25 views

An Nmap Script and Crontab

I have created a script that will run an Nmap scan, then go through the results and see what is different from past results. Then email the differences. I have been trying to get it to run ...
1
vote
1answer
38 views

Command works on terminal but doesn't work in cron [duplicate]

I have the following command that I can run from any folder and it will start my (Angularjs) webapp by using the grunt task runner tool - cd /root/dev/myapp && grunt serve However when I ...
0
votes
1answer
21 views

Where do I look for cron errors [duplicate]

I have 2 cron jobs that were running fine but now stopped running. I looked through my crontab and everything looks OK. How can I tell if these jobs are running? is there a place where cron stores ...
207
votes
4answers
399k views

Where is the cron / crontab log?

I want to verify if my cron job is executing and what time. I believe there is a log for my sudo crontab -e jobs, but where? I searched google and it I found references to look in /var/log ...
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0answers
31 views

Ubuntu shuts down unexpectedly, Every night

I know this sounds weird but unfortunately it's real. I have Ubuntu 14.04 LTS running on Dell Inspiron N5150 Laptop with intel i7 CPU and nvidia GeForce GPU. Every night between 9:30 pm and 11 pm ...
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2answers
54 views

.sh ffmpeg works manually, not with CRON

I make a movie from jpeg pictures with the script: #create movie ffmpeg -i /home/philippe/Dropbox/Public/Cheiron/day/%d.jpg -r 25 -q:a 5 -pix_fmt yuv420p ...
1
vote
1answer
37 views

Cron jobs with R scripts

I am trying to schedule cron job for an R script. I've read this question How do I set cron job and followed suggestions from first answer. I typed crontab -e In the command line and put there a ...
1
vote
1answer
57 views

What is messing up my system clock?

Ubuntu 14.04 desktop, 64-bit I came in to work this morning and noticed that the clock on my system was off by approximately 3 minutes, as compared to the clock on my phone. That seems odd, since my ...
2
votes
1answer
710 views

Why anacron does not call the crontab user files?

I want a special command to be lauched everyday, but dont want to put it in the /etc/cron.d/ because its a user specific user! pg@pipoTower: ~$ crontab -l # m h dom mon dow command 0 0 * * * ...
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votes
2answers
30 views

is it possible to rsync to another server using crontab?

Hi there is a bunch of videos and resources on how to rsync locally rsync /home/user1 /home/user2/backup, but i haven't found any tutorials on rsync crontab to another server pretty much, i use ...
0
votes
1answer
27 views

watch internet connection thoguh shell

I just need to run a shell script when an internet connection is available. Is it possible to watch the internet connection arability through Shell scripting. ping google.com is the easy command to ...
0
votes
0answers
12 views

cron.daily message - return code 100

I searched for a return code and found many similar but not this identical one. It's not an error per se, but I would like to know what it means. Email from root: Subject: Cron test -x ...
0
votes
1answer
125 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
0answers
74 views

How to wake up my Laptop from sleep (suspend) when AC charger connected

In my area, electricity turned off for some periods, so I configured my laptop to goes to sleep when battery percent 10%, but I want it to wake up after AC charger is charging on. is there any way to ...
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vote
0answers
32 views

Bleachbit cron problems

I've been trying to get gnome-schedule to automate bleachbit but the crons never work. So after trying a lot different things I decided to just try setting crons the normal way. I opened terminal and ...
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vote
0answers
26 views

Turn thinkpad screen off and back on automatically via cron

I setup my thinkpad a while back with ubuntu 10.10 to work as a digital picture frame and each night turn off the screen with a cron cron command, then in the morning another cron command turns it ...
2
votes
1answer
119 views

Recording a youtube live stream using vlc

I'm trying to set vlc to record a live stream on youtube using cron. Vlc records videos that aren't live streaming just fine, but when the stream is live vlc records at most only 24 seconds. Why ...
0
votes
0answers
21 views

How to Schedule Rsync over SSH (Ubuntu Server, Windows and OS X Clients) [duplicate]

On OS X I want to create a cron job that rsyncs certain folders to my Ubuntu server. I do something like this: MAILTO="my@email.com" */5 * * * * rsync -avz '/local folder/' ...
0
votes
1answer
327 views

How do I set up PHP and MySQL cronjobs on Ubuntu 12.04 (Precise Pangolin) server?

I just made a LAMP install and got SFTP working. My question now is: How do I set up cronjobs on Ubuntu server? I need to make some cronjobs for my PHP/MySQL application. I look for un-activated ...
6
votes
2answers
753 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: ...
0
votes
0answers
20 views

Cron job for running gedit not working [duplicate]

I'm trying to set up a cron job that fires up gedit and displays a file at a certain time every day, but it's not working for me. To test it, I entered a time 3 minutes into the future, like this ...
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vote
0answers
22 views

Why ps produce different output when it is started from a cron job?

When I run ps -f -u $USER ($USER is ubuntu) this is the output I get. USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND ubuntu 23517 0.0 0.1 22244 4856 pts/5 Ss+ ...
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votes
0answers
15 views

How does the system interprets sudoers file when there are two lines for the same user?

I have a system with a user already added to sudoers file with username ALL=(ALL:ALL) ALL Now I want to allow username to run a single script without asking for sudo password (cron job). This ...
0
votes
1answer
93 views

CRON doesn't run tasks because “/bin/bash: /var/log/cron.log: Permission denied”

I have the following CRON task: MAILTO="my@email.com" # Begin Whenever generated tasks for: projectname 30 4 * * * /bin/bash -l -c 'cd /home/deployer/apps/project_production/releases/20150305135322 ...
2
votes
1answer
54 views

can't find package crontab-ubuntu 12.04

I am trying to install cron for scheduling and before anyone says duplicate, I have tried the methods of sudo apt-get update and upgrade mentioned and they don't work. When I go to install crontab, ...
16
votes
6answers
38k views

How do you set the timezone for crontab?

I have set up ACPI wakeup so my laptop wakes up at a certain time each morning. The timezone for this is UTC. I want to set up my crontabs also using UTC so they fit with the wakeup alarm. How do ...
0
votes
0answers
58 views

Cron job not running at time intervals

I am new to using cron to automatically run a script. Currently, I have created a script to run every hour using the Configure Scheduled Tasks Manager. In the manager it allows me to instantly run a ...