Questions tagged [cron]
cron is a task scheduler based on clock time that runs on Linux-based machines.
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cron can't read PYTHONPATH environment variables?
I have added to the PYTHONPATH on my server's .bash_profile file. However it appears that cron isn't reading from it because I am getting import errors. If I run the exact command cron calls on the ...
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Which bash rc files are run on non-interactive/non-login shells?
My Understanding
there are no rc files called for non-interactive/non-login shells; for example, those run by cron
(I don't know this for certain and would lean on the community's expertise)
non-...
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how do i run a script 5mn after startup?
I have severals RoR websites running on my webserver and I need to run a ruby script at startup.
So, I puted a bash script in /etc/init.d witch call a ruby process.
Unfortunatly that ruby process ...
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BASH - merge directories when using mv
I just started using BASH, so I can move all contents of a directory to another. But the issue is, I was expecting it to merge the directories. I am using cron job to run this script.
#!/bin/bash
...
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Disable cron jobs for a specific user
I have a list of jobs in the crontabs for user1, user2. I want to prevent the jobs of user2 from running.
I tried listing user2 in cron.deny, but that only prevents him from accessing his crontab. ...
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Use cron to screen capture on Mac OS X
To analyze my own computer usage, not to spy on anyone (although it crossed my mind), I want to have cron capture the current screen every minute.
* * * * * /bin/bash -c "/usr/sbin/screencapture /...
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git push to github via cron on mac
I'm trying to use git push in a bash script being run by crontab to push a commit to github. At the end of the script I'm doing this:
# script processes some files, then:
git add -A
git commit -a -m "...
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cron apparently requires a newline character on its own line at the end of the file
I'm trying to understand why cron is refusing to work with a certain crontab file. The manpage for crontab says:
cron requires that each entry in a crontab end in a newline character. If the ...
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How can I write a cron job that will block my internet from 7pm to 7am? (So I can get some sleep)
I am using OSX 10.6 and it has cron built in. How can I write a cron job that will block my internet from 7pm to 7am every day?
Im sure this must be simple but I could only find one example online ...
user242065
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cron runs but nothing happens
I have created a script called "forward_email.sh" and set permissions to 777. It contains the following line:
echo "It worked: $(date)" >> /home/noc/email.log
I created a cron job with the ...
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Can Ubuntu play a video via cron job?
I'm developing a display system for a paint shop.
I've set up a computer with Ubuntu to run the video and display it on a TV, running a PHP script that should update the video every hour via the ...
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Ubuntu: how does cron execute jobs?
I am having trouble finding an answer to this question thorough google:
How exatly does CRON in ubuntu execute jobs?
Does it spawn each new job in its own process?
Say i have two cron jobs:
@...
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Having all systemd timers mail to root on error
cron sends an email to the crontab owner on job error.
How can i have systemd do the same when it runs a timer?
Note: I am not looking for a recipe for adding email notification to a specific service. ...
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How can I permanently fix my date synchronize problem in linux?
Ubuntu 7.10 server i386 clock/date/time won't stay in sync. Are their log files I can view to tell when the clock changes? For a temporary fix, I created a file in /etc/cron.hourly:
#!/bin/sh
ntpdate ...
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How to use @reboot for crontab with delay
In crontab, I can use @reboot to run a command after the system reboot. Is there a way to do this with an delay, i.e. run a command after 10 minutes of reboot?
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How to run webcam software only when I am not home (phone is not on the LAN)?
Currently I've got my user cron starting Motion on a timer when I typically leave for work, and then killing it when I typically get home, so I can watch my cat/burglars/etc:
0 9 * * * killall motion ...
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How to mail output of shell script as a cron job
I've created a cron job that runs a shell script. I'd like the shell script to run and capture it's output and have it emailed upon completion. Here's what I have so far, but the mail message body ...
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Why does root cron job script need 'sudo' to run properly?
I'm running this simple script on my Raspberry Pi to auto update so I can forget about it. It also keeps a log that says whether the update was successful. The script is update.sh:
#!/bin/bash
echo "...
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cron.weekly and cron.monthly run times
What day of the week does cron.weekly run on
What day of the month does cron.monthly run on?
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How to use variables in variables in crontab
I'm trying to use variables in variables in crontab:
AUTH=user:password
BASE_URL=http://...
COMMAND_OLDB=curl -u $AUTH $BASE_URL/openligadb >> /var/log/cron.openligadb.log
But just getting a ...
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Why does running Redshift commands from crontab does not seem to work?
About redshift:
Redshift adjusts the color temperature of your screen according to your surroundings.
A typical redshift command that I use is redshift -O 9999 which sets the screen color ...
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From what context is a cron task executed?
I am asking this question after royally destroying a Linux box. Let me give you some background so you know where I am coming from.
I currently have (well... did have) a RedHat Linux box running ...
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Nice commands in a .sh script for cron jobs
I have a php script that I need to run on shared webhosting.
I have created a cron job that executes an sh script. The command in my crontab is:
/bin/sh /home/user/script.sh
I'm assuming it is Bourne ...
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cron job when Ubuntu is suspended
I am using Ubuntu precise. Is there a way to have scheduled cron jobs run even when Ubuntu is suspended? Perhaps some way to automatically wake up the system so a scheduled cron job can proceed and ...
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How to handle daylight savings in cron jobs
I have a cron job on an amazon ec2 machine (Ubuntu 16.04) that is supposed to run at 2:00 AM Central time.
The cron job is scheduled using UTC time. Since Central time is currently UTC-5 (we are in ...
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Anacron, execute job as many times as it has been missed
If I schedule a job to be run at 3 A.M. every day and it is missed 3 days in a row, will Anacron execute it 3 times when the system comes back running, or only once ?
If it is only run once, is there ...
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Is there a aliases file for sSMTP?
I installed sSMTP for sending emails from command line.
I want to create some alias for cron jobs:
$ sudo vim /etc/aliases
# append this line at the end
myname: root
$ newaliases
newaliases:...
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with a shell script, it is possible to tell when it's run with cron vs run manually?
with a shell script, it is possible to tell when it's run with cron vs run manually?
UPDATE:
it was asked why I want to know. My cron job will be logging, and i want to be able to log if someone ...
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How do I automate borg backup?
Background
I would like to use Borg Backup as a backup solution for my Ubuntu server. They offer a very convenient sh script that they say you can just run as a cron job, but it is not working for ...
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Why doesn't cronjob execute feh command
I build a cronjob to download a new picture from a source every ten minutes and set it as wallpaper using feh. The file is downloaded but the wallpaper doesn't change. Where is the problem? crontab -e ...
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Delete all files older than X days
So I have a cron setup to make backups of a folder into a tarball every hour. I would like to add into the shell script that I'm using the ability to have files deleted automagically after about three ...
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Run Linux script at time 'n' on first day, 'n+15 mins' next day, and so on
I'm trying to take timelapse images using my webcam. What I want to do is run a script at midnight on 1st Jan, then 00:15 on 2nd Jan, 00:30, 3rd Jan and so on. This can keep running forever, I'll ...
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How can I add a timestamp to the end of a cron job's output file name?
I want to track each crontab output to separated file.
Normally, I use this as crontab entry:
1 * * * * root php /mix/dostuff.php > /tmp/dostuff.txt
Now, I want to make it to write ...
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crontab job log message shows a error status 0x004b from mta#012
The crontab job log message shows a error status 0x004b from mta#012 when I try to check my crontab job.
# grep CRON /var/log/syslog
[...]
I get this log:
Nov 26 08:00:01 stiitsrv9 CRON[26109]: (...
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How to run a script at boot time for normal user?
I want to run a bash script at boot time in CentOS 6. I added the script in /etc/init.d/ directory but all these script are run by root. I want to run script for any user.
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using either notify-send or zenity in Cron
I am trying to get cron to provide a screen alert when it spots a particular situation. I know the script is executed each minute but it will not display on the screen.
script executed is:
DISPLAY=:...
user28987
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How can I automatically take a screenshot of a website at a specified time? [closed]
I need to take a screenshot of a website automatically at a time specified by me. Ideally it would not be using my computer since it's not guaranteed to be on at the specified time.
Is there some ...
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Will cron.daily wait for jobs to finish before starting the next one?
This page http://wiki.ci.uchicago.edu/I2U2/WebalizerConfiguration
suggests renaming /etc/cron.daily/logrotate so it comes after /etc/cron.daily/webalizer - webalizer should be done before logrotate ...
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Open a terminal from a Crontab
How do I get a gnome-terminal window to open from a crontab?
I have tried this:
* * * * * /usr/bin/gnome-terminal
* * * * * source /home/user_name/.bashrc ; /usr/bin/gnome-terminal
* *...
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Can't use /usr/bin/security to retrieve password from keychain via cron
I can't seem to be able to successfully retrieve passwords from keychain using /usr/bin/security when I run it from my users crontab. Works fine in my terminal.
I can also see via the cron mail ...
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Cron ignoring an update to crontab
I've commented out a line in the crontab on a debian server, which I guess was there by default yet was causing me to get error emails every hour:
# m h dom mon dow user command
17 * * * * root ...
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mount and umount behaving differently when run under cron
Running CentOS 6 in AWS, and what I'm seeing is baffling me.
There is an s3fs mount in /etc/fstab that sometimes loses its ability to read and write from. I have a cron job that worked great for ...
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how do I see the history of crontab?
I've read a few posts on the web, gone and looked for the file they are mentioning and haven't found it. I'm in Ubuntu 11 and trying to troubleshoot a cron job that isn't running, even though I have ...
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Should I worry about Daylight saving time when planning to schedule backups?
So if there is a day:
https://secure.wikimedia.org/wikipedia/en/wiki/Daylight_saving_time
when we have to e.g.: set our clock back from 3am to 2am. Ok.
So if someone creates a cron job at 3am, ...
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rm failing inside cron script
I have a cron job calling a bash script which runs fine, except for one line inside it that is suppose to remove all fines in a directory. The result of this line is always 'no such file or directory' ...
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Linux startup script to connect to bluetooth and cron to keep it connected
I have a mini Bluetooth keyboard and a Raspberry Pi running a Debian-based distro. I know the MAC address of the keyboard but for this question, let’s just use AA:BB:CC:DD:EE:FF. Right now I have to ...
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Shell script of mysqldump works fine when run manually, but does not run in the cron job?
I have a shell script to get a MySQL database dump. This script works fine when run manually
#!/bin/sh
fqn=/home/Mysqluser/daily_dumps/bookstore_`date +%Y%m%d_%H%M%S`.sql.gz
mysqldump -u root -h ...
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How to use "date" to print tomorrow's day of the week
On CentOS 6 Linux I use date +%a in several cronjobs and scripts to generate logfile names like myprog-Tue.txt and this works well for me since many years.
But now for one program I need to delete ...
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Simple Linux-based task scheduler with job dependencies? [closed]
I'm maintaining a data-warehousing system that involves a lot of dependent jobs (data import, transform, etc). I've been using Linux's crontab to manage them until the dependency between jobs get ...
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How to create a cron job to upload files to an FTP server
I would like to create a cron job that uploads files from a directory on my computer to my FTP server. I would like it to do it daily at midnight. I know pretty much nothing about cron, so I ...
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