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

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101 views

Is it possible to use the at command to schedule a job to run at a given timestamp?

I want to schedule a file to run using the at command, as described in this tutorial. I see that the at command supports the posix format -- but I don't see any mention of timestamps. Surely it is ...
3
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1answer
843 views

How to switch tty with a script / cronjob

Is it possible to switch the current tty/vt with the help of a bash script or a cronjob? I only know the physical keyboard input "Ctrl-Alt-Fx". I would like to show two virtual desktops at different ...
3
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1answer
525 views

Running time command with cron

So I have a crontab that have this line: 30 16 * * * (time sysbench --test=cpu --cpu-max-prime=20000 run) 2>> ~/cpu.out I use this because time output goes by default to stderr and I want to ...
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3answers
4k 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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2answers
630 views

Can I use variables in crontab file?

I mean I want to use this variable at "minute to wday" in the following. minute hour mday month wday who command Because I want to set these values in some configuration file and want ...
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3answers
3k views

How to schedule something run once using anacron?

Frequently within my scripts I schedule auxiliary tasks for later in the form: at now + 8 hours <<< "rm -f workfile.$$ >> $worklog 2>&1 " or at 11pm + $(date +%M) minutes ...
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2answers
9k views

List currently running cron tab and stop it

I created a cronjob, it runs for a very long time but now don't know how to stop it. Please help.
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1answer
35 views

Why am I seeing much more cron jobs in webmin than in `crontab -e`?

I am just starting to learn cron jobs. Basically I am going to use webmin to manage my cron jobs, I am also reading some basic information about cron jobs. So far I've learned that /etc/crontab ...
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1answer
27 views

How would you build a cron that empties the mail in all mailboxes?

I am new to Unix here. We have some mailboxes that are taking up an incredible amount of space and I'm trying to figure out a way to delete all mail that has been in the box for 30 days. Most of what ...
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1answer
206 views

How to run free command by crontab

I want to run this command: free && sync && echo 3 > /proc/sys/vm/drop_caches && free -m by cron. That way I can free my RAM and cache in an Ubuntu system. I'm using ...
3
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1answer
757 views

Regex for crontab validation

I need to check in bash whether an entry into the crontab file is valid. Is there a crontab command switch? I can extract individual lines and try to control individual items through regex. But I ...
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4answers
439 views

Only allow process to run between hours x and y

I use a mobile data connection service. I only have unrestricted bandwidth between 9am and 4pm. I wonder how I can "silence" applications such as the Dropbox applet outside that schedule. I thought ...
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2answers
19k 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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2answers
2k views

crontab exclude specific date only

How can I write a cron that will exclude a specific date. let say : I need to run a crontab 6pm to 9pm in every 30 min on weekends and want to exclude 10th may 2014 only. Is It possible? How can I ...
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3answers
3k views

Solaris: how to forward cron e-mails?

If a cron job produces output it is e-mailed to the user's account. I would like to redirect this e-mail to another e-mail account. Preferably on a user-by-user basis. I've looked into some options ...
3
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1answer
442 views

Cron job results are different from executing from own shell

I am using Ubuntu 12.0.4 I have a script basically with the following codes: lockfile=/var/tmp/mylock if ( set -o noclobber; echo "$$" > "$lockfile") 2> /dev/null; then exit_normally ...
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2answers
921 views

Automatic Update Script using Cron, Exit Codes, and Logging

I'm managing multiple machines running Debian, Raspian, and Mint. On some of the machines I want to have updating and upgrading automatically. I've drafted a script that I want to do this and log if ...
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2answers
2k views

How do I check active crons?

I'm trying to hunt down a cron job (or the equivalent) which I know is running, but I can't find it in the default cron files for my system (FreeBSD / Linux / BSD). How can I tell which ones are ...
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1answer
3k views

Maximum Number of Entries in Crontab

If it exists, what is the maximum number of cron jobs (entries?) that can be added to a server's crontab? How do I tell? I'm on RHEL 6. I googled around, but did not see a conclusive answer -- some ...
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1answer
824 views

Scheduled task on reboot

How can I schedule a task to run on next reboot? I understand that we have tools like cron and at to help with scheduling. But they seem to allow scheduling at a specific time and not on specific ...
3
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1answer
40 views

Using zip package for debian with password

I'm trying to make a backup .sh script to zip my files and to protect the zip archive with a password. For that, I'm using the zip package (apt-get install zip) and there's an encryption option ...
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2answers
43 views

Control character handling in cron/mailx

I have a cron job which runs a long script producing lots of output. Some of the output is lines delimited by single carriage returns; when run from the command line, these make the successive lines ...
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1answer
125 views

What could be happening between pidof and kill to cause “no such process”?

I've inherited quite a bit of code and am looking at a cron job that restarts a service once an hour, no other scripts touch this process and this code is ran. #The name of the process has been ...
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2answers
113 views

Find and rm command not obeying exclude list occassionally

I am running a find and rm -rf directory list modified earlier than 7 days with an exclusion list of directories which should not be deleted at any case. This is the script excerpt find ...
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1answer
3k views

Cron job, random start but within timeframe

I want a script to run once a day, everyday, starting any time between 0900 and 1200. I'm not completely sure about the dash syntax - does it mean that the script will run EVERY hour between 9-12, or ...
3
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1answer
56 views

fault-tolerant crond replacement

I'm looking for a replacement to crond, or possibly an extension of it. The feature that I definitely would want to have is fault-tolerance. E.g. if a job failed to run due to the computer not being ...
3
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1answer
315 views

What's the easiest way to set up a 2-hour alarm?

I want my computer to play some given .mp3 every 2 hours. I want it to run at startup, and be modifiable with a given .conf file. The choice of .mp3 will also be in the .conf file. The reason is, I ...
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1answer
3k views

Daily logRotate for apache at specific time

How can I execute logRotate daily at a specific time (3h30) each day? Specific details on how to do this would be appreciated. I'm on Debian.
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1answer
4k views

Crontab + Ruby on Rails: /usr/bin/env: ruby: No such file or directory

I have a ruby on rails app and I need to schedule a crontab for a rake task. */5 * * * * RAILS_ENV=production /usr/local/bin/rake -f /usr/local/www/mysite-web-production/current/Rakefile ...
3
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1answer
2k views

How to add crontab in FreeBSD

I am trying to add a job to my crontab in FreeBSD but it is not working : I have used this to add the job: sudo crontab -e -u vaibhav @daily /home/vaibhav/applications/comparison/scrapy but it is ...
3
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1answer
250 views

Executing 'ssh-add -D' from a cron job doesn't work

I've set up an openSSH server on an ubuntu-server machine, and I configured it to use public/private key (without password). I want to require both password and key check when the client connects to ...
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4answers
6k views

How to display a (zenity/GUI) dialog to the user after a root cron task has completed

I have a simple periodic cron task that must run as root. I want to use Zenity (or similar) to display a GUI informational dialog to user 1000 (or logged in user or all users) when the cron task ...
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2answers
2k views

Bash script doesn't work as cronjob

I'm trying to get this simple bash script to work within a cronjob. It's used to generate static nginx webserver statistic pages using GoAccess. I tried everything I know to resolve this issue, it ...
3
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1answer
377 views

ipsec auto --status fails in cronjob

I have a server monitoring script which, among other things, checks the state of an IPSec tunnel using ipsec auto --status It works like a charm when run from the console (as root) but as soon as I ...
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2answers
96 views

Crontab shell script git pull and forever start

I'm trying to set up a Raspberry Pi to check a repo on startup and then fire up a node script with forever. I got the second part working, but I tried a dozen git commands with no success. Here is ...
3
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1answer
60 views

Soft raid1 schedule resync

Debian has a cronjob /etc/cron.d/mdadm that starts a raid check (& resync?). It costs a lot of IO and can take up to 96 hours on 3TB disks. At this time the performance of the service will go ...
3
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1answer
487 views

Cron can't access my home directory when I'm logged out

I have quite a strange problem using cron. I distilled it thus far: I created following simple bash script in /home/user1/cron_dir/cron.sh: #!/bin/bash echo "Success" As user1 I created following ...
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2answers
146 views

How to run a command as if it is called from cron

I write a script and set it as a cron job. But due to a difference of environment variables it doesn't work as it should be. In that case I change a little bit with crontab -e and set a cron job time ...
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2answers
2k views

Crontab change MAILTO for only one specific job in Root's crontab

Can I do the following to change where mail goes for one specific crontab job in root's crontab (don't sent to root for Do Something job, just send to porklover): # Make a hambone appear * * * * * ...
3
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1answer
3k views

Is there a update manager whitout gnome dependencies for xfce?

I'm looking a update manager for Debian Xfce. I installed xfce on a computer which will be use by laypersons. Therefore, I want another way (graphical) to launch apt-get update && apt-get ...
3
votes
1answer
3k views

Why does sftp hide the log from stdout?

I have a script a.sh, which has an sftp command: echo "Starting to sftp..." sftp xxx@xxx.xxx.xxx.xx << END_SCRIPT ls mput *.csv.gz bye END_SCRIPT echo "Sftp successfully." If I run it ...
3
votes
1answer
28 views

How to one way sync two folders on startup

I am trying to synchronize: /var/www/CI_MAIN/ according to the changes made in: /home/coco/workspace/CI_MAIN/ (PDT's workspace). To do this, I entered sudo crontab -e in the command ...
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0answers
103 views

How do I schedule a cron task to run

I'm looking to crontab a script every hour starting Friday at 5pm... ending Monday at 5am. This script checks if it's completed this week and if it's currently running. If no/no, start task. Off the ...
3
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3answers
425 views

Detecting cron tasks run by another user

I am currently working through the Nebula challenges on exploit-exercises.com, and one of the challenges relies on a script being run by cron. This is run by another user (flag03) and the user I am ...
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2answers
932 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 ...
3
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1answer
625 views

How do I push a Mercurial repository to BitBucket over ssh? [closed]

I created a public key for ssh and registered that key with BitBucket. I then attempted to push: $ hg push ssh://jhayward@bitbucket.org/johncharrell/[project name] pushing to ...
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3answers
6k views

/etc/crontab what does “test -x” stand for

In my /etc/crontab file I have: # m h dom mon dow user command 17 * * * * root cd / && run-parts --report /etc/cron.hourly 25 6 * * * root test -x /usr/sbin/anacron || ( cd / ...
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5answers
235 views

crontab -e not working

I'm running these commands on crontab and it seems that the script are not running every 5 minutes 5 * * * /etc/my_scripts/telnet.sh | telnet >> /tmp/top_Jay.txt 5 * * * ...
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3answers
270 views

Crontab syntax: using '*' for minutes value

What happens if I use '*' for the minutes value? Is the command going to be run every minute? For example: * 4 * * 0 <command>
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2answers
801 views

Is it possible to schedule a cron job to run fortnightly?

Is there a way to schedule a cron job to run every fortnight? (One way I can think of, within crontab, would be to add two entries for "date-of-month"...)