i want to execute a script twice daily at 00:00 and 13:30 so i write :

    0,30 0,13 * * *

it seems wrong for me, because like this, the script will fire at 00:00 , 00:30 , 13:00 and 13:30. Any idea ?

execute crontab twice daily at 00h and 13:30

I&#39;m trying to figure out how to run a crontab job every week on Sunday. I think the following should work, but I&#39;m not sure if I understand correctly. Is the following correct?

    5 8 * * 6


How to run crontab job every week on Sunday

Is this correct scheduled to run between 07:00 and 19:00 at every 15 minutes?

    */15    07-19        *     * *     /path/script

crontab run every 15 minutes between certain hours

I am new to scheduling tasks with cron and crontab.  I am trying to schedule execution of a task as if I had logged on, opened a terminal, and executed it myself.

However, I scheduled a task to help me observe what $USER and $PATH a scheduled task is executing with, and this is what I found:

    $ crontab -l
    41 11 * * * echo &quot;USER: $USER&quot; &gt; ~/Desktop/cron_env.log; echo &quot;PATH: $PATH&quot; &gt;&gt; ~/Desktop/cron_env.log
    $ cat ~/Desktop/cron_env.log
    USER:
    PATH: /usr/bin:/bin

It appears as though $USER is not set, and $PATH is something very basic and/or default.  On the contrary, this is what I see when I open a terminal (logged in) and echo this same information:

    USER: aschirma
    PATH: /usr/lib/jvm/java-6-sun/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/pkg/icetools/bin:/pkg/hwtools/bin:/pkg/netscape/bin:/pkg/gnu/bin

What do I need to do to make my crontab tasks run the way I want?

crontab PATH and USER

I&#39;m trying to add a line to the crontab on Ubuntu.

Right now, I&#39;m doing `crontab -e` and editing the crontab there.

However, I can&#39;t seem to find the real crontab file, since `crontab -e` seems to give you a temporary working copy.

`/etc/crontab` looks like the system crontab.

What is the path of the crontab that `crontab -e` saves to?

Thanks!

Appending to crontab with a shell script on Ubuntu

I&#39;m learning node.js and just set up an empty Linux Virtual Machine and installed node.

I&#39;m running a function constantly every minute 

    var request = require(&#39;request&#39;)
    var minutes = 1, the_interval = minutes * 60 * 1000

    setInterval(function() {
        // Run code
      })
    }, the_interval);


And considering adding some other functions based on current time. - (e.g. run function if dateTime = Sunday at noon)

My question is are there any disadvantages to running a set up like this compared to a traditional cron job set up?

Keep in mind I have to run this function in node every minute anyways.

Set Interval in Node.js vs. Cron Job?

In crontab does the Day of the Week field run from `0 - 6` or `1 -7`?

I am seeing conflicting information on this.  wikipedia states `0-6` and other sites I have seen are `1-7`.

Also what would be the implication or either using `0` or `7` incorrectly?  i.e. would the cron still run?

Crontab Day of the Week syntax

I would like to set a job to run daily in the root crontab. But I would like it to execute it from a particular directory so it can find all the files it needs, since the application has a bunch of relative paths.

Anyway, can I tell crontab to run from a particular directory?

Crontab - Run in directory

I need to add a cron job thru a script I run to set up a server. I am currently using Ubuntu. I can use `crontab -e` but that will open an editor to edit the current crontab. I want to do this programmatically.

Is it possible to do so?

How do I create a crontab through a script

I have few crontab jobs that run under root, but that gives me some problems. For example all folders created in process of that cron job are under user root and group root. 
How can i make it to run under user www-data and group www-data so when i run scripts from my website i can manipulate those folders and files?

My server runs on Ubuntu.  
Current crontab job is:  

    */1 * * * * php5 /var/www/web/includes/crontab/queue_process.php &gt;&gt; /var/www/web/includes/crontab/queue.log 2&gt;&amp;1

How to specify in crontab by what user to run script?

Is it possible to use PHP to create, edit and delete crontab jobs?

I know how to list the current crontab jobs of the Apache user:

    $output = shell_exec(&#39;crontab -l&#39;);
    echo $output;

But how to add a cron job with PHP? &#39;crontab -e&#39; would just open a text editor and you will have to manually edit the entries before saving the file.

And how to delete a cron job with PHP? Again you have to manually do this by &#39;crontab -e&#39;.

With a job string like this:

    $job = &#39;0 */2 * * * /usr/bin/php5 /home/user1/work.php&#39;;

How do I add it to the crontab jobs list with PHP?

Use PHP to create, edit and delete crontab jobs?

Some cygwin commands are `.exe` files, so you can run them with the standard Windows Scheduler, but others don&#39;t have an `.exe` extension so can&#39;t be run from DOS (it seems like). 

For example I want `updatedb` to run nightly.

How do I make cron work?

How do you run a crontab in Cygwin on Windows?

I need to set up a cron job that runs an executable compiled using gcc once every hour.

I logged in as root and typed `crontab -e`

Then I entered the following and saved the file.

    0 * * * *  /path_to_executable

However, the cron job does not work.

I see that when I type `/...path_to_executable` I get a segmentation fault.
I can only execute the executable from the folder it is located in.
Is there a way I can solve this problem?

How to set up a cron job to run an executable every hour?

I recently setup a Laravel Queue system. The basics are a cronjob calls a command which adds jobs to a queue and calls a second command which sends an email. 

The system works when I ssh into my server and run php artisan queue:listen, but if I close my terminal the listener shuts down and the jobs stack up  and sit in queue until I ssh back in and run listen again.

What is the best way to keep my queue system running in the background without needing to keep my connection open via ssh?

I tried running `php artisan queue:work --daemon`, and it completed the jobs in the queue, but when I closed my terminal it closed the connection and the background process.



How to keep Laravel Queue system running on server

I would like to know if there is a way to setup a cronjob/task to execute every minute. Currently any of my instances should be able to run this task.

This is what I have tried to do in the config files without success:

    container_commands:
      01cronjobs:
        command: echo &quot;*/1 * * * * root php /etc/httpd/myscript.php&quot;

I&#39;m not really sure if this is the correct way to do it

Any ideas?


AWS Elastic Beanstalk, running a cronjob

I am having problems with getting a `crontab` to work. I want to automate a MySQL database backup.

The setup:

 - Debian GNU/Linux 7.3 (wheezy) 
 - MySQL Server version: 5.5.33-0+wheezy1(Debian) 
 - directories user, backup and backup2 have 755 permission
 - The user names for MySQL db and Debian account are the same

From the shell this command works

	mysqldump -u user -p[user_password] [database_name] | gzip &gt; dumpfilename.sql.gz


When I place this in a crontab using crontab -e 

	* * /usr/bin/mysqldump -u user -pupasswd mydatabase | gzip&gt; /home/user/backup/mydatabase-backup-`date +\%m\%d_\%Y`.sql.gz &gt;/dev/null 2&gt;&amp;1

A file is created every minute in /home/user/backup directory, but has 0 bytes.
 
However when I redirect this output to a second directory, backup2, I note that the proper mysqldumpfile duly compressed is created in it. I am unable to figure what is the mistake that I am making that results in a 0 byte file in the first directory and the expected output in the second directory.

	* * /usr/bin/mysqldump -u user -pupasswd my-database | gzip&gt; /home/user/backup/mydatabase-backup-`date +\%m\%d_\%Y`.sql.gz &gt;/home/user/backup2/mydatabase-backup-`date +\%m\%d_\%Y`.sql.gz 2&gt;&amp;1

I would greatly appreciate an explanation.

Thanks



mysqldump &amp; gzip commands to properly create a compressed file of a MySQL database using crontab

I am running next command within a crontab to encrypt a file and I don&#39;t want a keyboard interaction

    echo &quot;PASSPHRASE&quot; | gpg --passphrase-fd 0 -r USER --encrypt FILENAME.TXT

but I have this answer:

    gpg: C042XXXX: There is no assurance this key belongs to the named user
    
    pub  40XXX/C042XXXX 2012-01-11 Name LastName. (comment) &lt;user@email.com&gt;
     Primary key fingerprint: XXXX XXXX XXXX XXXX XXXX  XXXX XXXX XXXX XXXX XXXX
          Subkey fingerprint: XXXX XXXX XXXX XXXX XXXX  XXXX XXXX XXXX XXXX XXXX
    
    It is NOT certain that the key belongs to the person named
    in the user ID.  If you *really* know what you are doing,
    you may answer the next question with yes.
    
    Use this key anyway? (y/N) 

gpg encrypt file without keyboard interaction

Right now i am running my cron job everyday at 3.00PM

    0    15    *    *    *

But I want to run my cron job twice in a day. 10.30AM and 2.30PM

    0    30 10    *    *    *

I believe this command will run at 10.30AM. How should i run it in 2.30PM?

Run CRON job everyday at specific time

I&#39;m trying to create a cronjob to back up my database every night before something catastrophic happens. It looks like this command should meet my needs:

    0 3 * * * pg_dump dbname | gzip &gt; ~/backup/db/$(date +%Y-%m-%d).psql.gz

Except after running that, it expects me to type in a password. I can&#39;t do that if I run it from cron. How can I pass one in automatically?

How to pass in password to pg_dump?

In crontab, I can use an asterisk to mean every value, or &quot;*/2&quot; to mean every even value.

Is there a way to specify every **odd** value? (Would something like &quot;1+*/2&quot; work?)

Specifying &quot;all odd values&quot; in crontab?

Quite simply, I have node script that I want to execute once a month.

    30 6 1 * * node /home/steve/example/script.js

But this doesn&#39;t work, presumably because of path or the shell the command is being ran under. I&#39;ve tried the following means of executing node via cron (tested with -v):

    steve@atom:~$ node -v
    v0.4.2

    steve@atom:~$ sh node -v
    sh: Can&#39;t open node

    steve@atom:~$ bash node -v
    /usr/local/bin/node: /usr/local/bin/node: cannot execute binary file

    steve@atom:~$ /usr/local/bin/node -v
    v0.4.2

    steve@atom:~$ sh /usr/local/bin/node -v
    /usr/local/bin/node: 1: Syntax error: &quot;(&quot; unexpected

    steve@atom:~$ bash /usr/local/bin/node -v
    /usr/local/bin/node: /usr/local/bin/node: cannot execute binary file

I&#39;ve ran out of ideas to try, any advice?

How can you execute a Node.js script via a cron job?

I am familiar to setup the cron scheduler using `crontab -e` command on my `centos`. But today I found one of my `centos` servers doesn&#39;t have this command

I have tried to install this using `yum install crontab` but no luck. Then I tried `yum install crontabs` and it installed something

    =============================================================================
     Package                 Arch       Version          Repository        Size 
    =============================================================================
    Updating:
     crontabs                noarch     1.10-11.el5      base              7.0 k
    
    Transaction Summary
    =============================================================================
    Install      0 Package(s)         
    Update       1 Package(s)         
    Remove       0 Package(s)         
    
    Total download size: 7.0 k
    Is this ok [y/N]:

But still the `crontab` command doesn&#39;t work. If I do `cat /etc/crontab` then it shows below thing

    SHELL=/bin/bash
    PATH=/sbin:/bin:/usr/sbin:/usr/bin
    MAILTO=root
    HOME=/
    
    # run-parts
    40 * * * * root run-parts /etc/cron.hourly
    54 1 * * * root run-parts /etc/cron.daily
    14 3 * * 0 root run-parts /etc/cron.weekly
    38 1 16 * * root run-parts /etc/cron.monthly

What should I do to have `crontab` on that particular server? I am using `CentOS release 5.2 (Final)`.

grep on cron shows:

    [root~]# ps -ef | grep cron
    root     24022 24001  0 19:07 pts/1    00:00:00 grep cron

starting cron service returns: 
   
    [root~]# service cron start
    cron: unrecognized service

How to install crontab on Centos

Source Wikipedia:   

&gt; **Question mark** (?) is used instead of &#39;*&#39; for leaving either day-of-month or day-of-week blank.

The above statement is not making much sense to me.

So if I write some cron as **`0 0 0 ? * *`** then does it mean first of every month or it means it will execute daily?

It is a bit confusing as Java crons start with seconds while other crons start with minute.

Significance of question mark in Java cron

How to configure a cron job to run every night at 2:30? I know how to make it run at 2, but not 2:30.

Running a cron job at 2:30 AM everyday

How do &quot;modern&quot; `cron` daemons *internally* schedule their jobs?  Some `crond`s used to schedule a run every so often via `at`.  So after a crontab is written out, does `crond`:

 1. Parse the crontab for all future events and the sleep for the intervals?
 2. Poll an aggregated crontab database every minute to determine if the current time matches the schedule pattern?
 3.  Other?

Thanks,



How does cron internally schedule jobs?

Is this the correct way for setting a cron job to run every 3 hours? 
After setting it this way, cron is executing the command every minute.

![enter image description here][1]


  [1]: http://i.stack.imgur.com/ZnfnV.png

How to set a cron job to run every 3 hours

I have a crontab running every hour. The user running it has environment variabless in the `.bash_profile` that work when the user runs the job from the terminal, however, obviously these don&#39;t get picked up by crontab when it runs.

I&#39;ve tried setting them in `.profile` and `.bashrc` but they still don&#39;t seem to get picked up. Does anyone know where I can put environment vars that crontab can pick up?


Where can I set environment variables that crontab will use?

I need a crontab syntax which should execute a specific PHP script `/var/www/html/a.php` every minute. The execution on every minute must start at 00:00. The other task which must execute a script at 00:00 `/var/www/html/reset.php` (once every 24 hours).

All Crontab Solutions on Gang of Coders

Total of 28 Crontab Solutions