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== Background ==
== Background ==


==== Skills required  ====
See [http://en.wikipedia.org/wiki/Cron Cron on Wikipedia]


You must be able to connect to your qnap using telnet and edit using vi.
=== Skills required ===


==== crontab  ====
You must be able to connect to your QNAP device using [[How_to_SSH_into_your_QNAP_device|SSH]] and edit using a text editor such as [[Using_vi|vi]] or nano.


The crontab can be used to execute tasks (scripts) based on a reoccuring schedule; by default the crontab is used, for example, to restart the webserver during the night.
=== crontab ===


To view the content of the crontab, login to your qnap using telnet and type:  
The crontab can be used to execute tasks (scripts) based on a recurring schedule. The crontab is used, for example, to restart the webserver during the night.
 
To view the content of your crontab, login to your QNAP via SSH and type:
<pre>crontab -l
<pre>crontab -l
</pre>  
</pre>
You will see a (small) list of crontab entries.


Editing the crontab is also easy, on the console type:
You will see a (small) list of crontab entries.
<pre>crontab -e</pre>
The crontab will be shown inside a vi session. Edit the crontab as you wish.  


Once you have edited the crontab, execute the following to activate it:
<pre>/etc/init.d/crond.sh restart</pre>
See [http://en.wikipedia.org/wiki/Cron Cron on Wikipedia]


== Stock crontab jobs  ==


When using crontab -l on a default QNAP, QNAPs has some default crontab jobs.
== Standard crontab jobs ==


Usually you will want to know, what default jobs are running on the QNAP based on schedule.<br>
The following table contains the standard QNAP jobs that run on schedules.


The following table is meant to bring some light into those built-in jobs.The list is by no means complete, jobs may depend on the firmware version, start times may vary. If you find a job on your QNAP, that is missing in the table, add it. The list could help to identify unwanted jobs on the QNAP&nbsp;that regularly wake up your harddisk(s).<br>
This list is by no means complete. Jobs may depend on the firmware version, start times may vary. If you find a job on your QNAP, that is missing from the table, add it. The list could help to identify unwanted jobs that regularly wake up your harddisk(s).


{| width="100%" cellspacing="1" cellpadding="1" border="1"
{| cellspacing="1" cellpadding="1" border="1" width="100%"
|-
|-
! scope="col" | Default Time<br>  
! scope="col" | Default Time<br/>
! scope="col" | Job<br>  
! scope="col" | Job<br/>
! scope="col" | Explanation<br>
! scope="col" | Explanation<br/>
|-
|-
| 0 4 * * *  
| 0 4 * * *<br/>
| /sbin/hwclock -s  
| /sbin/hwclock -s
| http://linux.die.net/man/8/hwclock<br>
| [http://linux.die.net/man/8/hwclock http://linux.die.net/man/8/hwclock]<br/>
|-
|-
| 0 3 * * *  
| 0 3 * * *
| /sbin/vs_refresh  
| /sbin/vs_refresh
| vs_refresh is for share folder space usage calculation (for Network Share Management)<br>
| vs_refresh is for share folder space usage calculation (for Network Share Management)<br/>
|-
|-
| 0 3 * * 0  
| 0 3 * * 0<br/>
| /etc/init.d/idmap.sh dump  
| /etc/init.d/idmap.sh dump
| related to SAMBA Active Directory configuration. Used if security is set to ADS.<br>
| related to SAMBA Active Directory configuration. Used if security is set to ADS.<br/>
|-
|-
| 0 3 * * *  
| 0 3 * * *<br/>
| /sbin/clean_reset_pwd  
| /sbin/clean_reset_pwd
| (unclear) might be the new behaviour of the network recycle bin (purging files after a certain amount of days)<br>
| (unclear) might be the new behaviour of the network recycle bin (purging files after a certain amount of days)<br/>
|-
|-
| 0-59/15 * * * *  
| 0-59/15 * * * *<br/>
| /etc/init.d/nss2_dusg.sh  
| /etc/init.d/nss2_dusg.sh
| is a job of the Surveillance Station<br>
| is a job of the Surveillance Station<br/>
|-
|-
| 10 15 * * *  
| 10 15 * * *
| /usr/bin/power_clean -c 2&gt;/dev/null  
| /usr/bin/power_clean -c 2>/dev/null
| &nbsp;?<br>
| &nbsp;?<br/>
|-
|-
| 4 3 * * 3  
| 4 3 * * 3
| /etc/init.d/backup_conf.sh  
| /etc/init.d/backup_conf.sh
| does an automatic backup of several config files in /etc/config. <br>
| does an automatic backup of several config files in /etc/config.<br/>
|-
|-
| 0 3 * * * <br>  
| 0 3 * * *<br/>
| /bin/rm -rf /mnt/HDA_ROOT/twonkymedia/twonkymedia.db/cache/*<br>  
| /bin/rm -rf /mnt/HDA_ROOT/twonkymedia/twonkymedia.db/cache/*<br/>
| Will clear the Twonky media cache<br>
| Will clear the Twonky media cache<br/>
|-
|-
| 5 0 * * 1<br>  
| 5 0 * * 1<br/>
| /etc/init.d/antivirus.sh scan 1<br>  
| /etc/init.d/antivirus.sh scan 1<br/>
| If Antivirus is enabled, this will scan the files for viruses<br>
| If Antivirus is enabled, this will scan the files for viruses<br/>
|-
|-
| 0 0 * * *<br>  
| 0 0 * * *<br/>
| /etc/init.d/antivirus.sh archive_log<br>  
| /etc/init.d/antivirus.sh archive_log<br/>
| If Antivirus report jobs are enabled<br>
| If Antivirus report jobs are enabled<br/>
|-
|-
| 0 0 */1 * *<br>  
| 0 0 */1 * *<br/>
| /etc/init.d/antivirus.sh update_db<br>  
| /etc/init.d/antivirus.sh update_db<br/>
| If Antivirus is enabled, this will check&nbsp; clamav.net for updates<br>
| If Antivirus is enabled, this will check&nbsp; clamav.net for updates<br/>
|-
|-
| <br>  
| <br/>
| /etc/init.d/startup<br>  
| /etc/init.d/startup<br/>
| If a restart/powerof job is configured in power management<br>
| If a restart/powerof job is configured in power management<br/>
|-
|-
| <br>  
| <br/>
| /etc/init.d/poweroff<br>  
| /etc/init.d/poweroff<br/>
| If a restart/powerof job is configured in power management<br>
| If a restart/powerof job is configured in power management<br/>
|}
|}


<br>


== Method 1: /etc/config/crontab  ==


Edit /etc/config/crontab directly, then tell the cron service to reload the crontab. These changes will persist past a reboot so '''be careful!'''
== Adding entries at the command-line ==
Here are a couple of examples that append new entries to the crontab file:<pre>echo "1 4 * * * /share/custom/scripts/custom1.sh" >> /etc/config/crontab
echo "40 5 * * * /share/custom/scripts/custom2.sh" >> /etc/config/crontab</pre>


Here is an example which assumes you are ssh'd / telnet'd into your nas (as admin).
<pre>echo "1 4 * * * /share/custom/scripts/custom1.sh" &gt;&gt; /etc/config/crontab
echo "40 5 * * * /share/custom/scripts/custom2.sh" &gt;&gt; /etc/config/crontab
crontab /etc/config/crontab</pre>
== Method 2: autorun.sh  ==


''Some peoples have reported this method as the working method and others have reported that this does not. Perhaps it is an outdated way to add cron jobs.''


<br> Editing the crontab directly using 'crontab -e' as described above is possible on the QNAPs and it will function as expected. However as soon as your QNAP is restarted, you will be surprised to learn that all your custom entries will be gone from the crontab!
== Modifying entries ==


<br> To prevent the loss of your work, use [[Autorun.sh]] or [http://www.qnap.box.cx/ AutoRunMaster] and a custom script for changing the crontab:  
'''<span style="color:red">Do NOT edit crontab the usual way!</span>'''
<pre>#!/bin/sh
# location: /share/custom/scripts/contab.sh
# script name: crontab script
# purpose: add entries to the crontab, which will survive a QNAP reboot
# designed for Qnap TS-201
tmpfile=/tmp/crontab.tmp


# read crontab and remove custom entries (usually not there since after a reboot
On a desktop or server distribution, you would edit a user's crontab with:
# QNAP restores to default crontab:
<pre>crontab -e</pre>
crontab -l | grep -vi "custom1.sh" | grep -vi "custom2.sh" &gt; $tmpfile


# add custom entries to crontab
However, due to the way the QNAP firmware updates crontab, it will be '''overwritten''' on the next reboot. Obviously, you want your automation to survive reboots, so edit the crontab file directly with your text editor:
echo "1 4 * * * /share/custom/scripts/custom1.sh" &gt;&gt; $tmpfile
<pre>vi /etc/config/crontab</pre>
echo "40 5 * * * /share/custom/scripts/custom2.sh" &gt;&gt; $tmpfile


#load crontab from file
or
crontab $tmpfile
<pre>nano /etc/config/crontab</pre>


# remove temporary file
rm $tmpfile


# restart crontab
/etc/init.d/crond.sh restart
</pre>
Make sure your script is called when the qnap is started by adding it to [[Autorun.sh]] or by using [http://www.qnap.box.cx/ AutoRunMaster]


<br>
== Restart the daemon ==


== Method 1 bis:&nbsp; /etc/config/crontab, load and restart&nbsp;  ==
When you're done, reload the crontab file and restart the cron daemon:
<pre>crontab /etc/config/crontab && /etc/init.d/crond.sh restart</pre>


In a post on&nbsp;[http://forum.qnap.com/viewtopic.php?f=144&t=32519&p=253371#p253371 http://forum.qnap.com/viewtopic.php?f=144&amp;t=32519&amp;p=253371#p253371]&nbsp;Micke writes&nbsp;:


<br>


Don't bother with that kind of script at all. Whenever you add a custom entry then follow this procedure
== Notes ==
<blockquote>1. Edit /etc/config/crontab and add your custom entry. <br>2. Run 'crontab /etc/config/crontab' to load the changes.<br>3. Restart cron, i.e. '/etc/init.d/crond.sh restart' </blockquote>
If you follow this procedure then the changes survive a reboot (even a firmware upgrade), i.e. no need for any script to restore them.


/Mike<br>  
Don't forget to make your scripts executable! Otherwise they will silently fail! You tested your script, right?
<pre>chmod +x filename.sh</pre>


Tested on 3.6.0&nbsp;: works fine.&nbsp;


[[Category:Miscellaneous]]
<div><span style="font-size:smaller">''These instructions have been tested on various versions of QNAP firmware from 3.6.0 onwards.''</span><br/></div> [[Category:Adding new services]]

Latest revision as of 16:49, 12 December 2016

Background

See Cron on Wikipedia

Skills required

You must be able to connect to your QNAP device using SSH and edit using a text editor such as vi or nano.

crontab

The crontab can be used to execute tasks (scripts) based on a recurring schedule. The crontab is used, for example, to restart the webserver during the night.

To view the content of your crontab, login to your QNAP via SSH and type:

crontab -l

You will see a (small) list of crontab entries.


Standard crontab jobs

The following table contains the standard QNAP jobs that run on schedules.

This list is by no means complete. Jobs may depend on the firmware version, start times may vary. If you find a job on your QNAP, that is missing from the table, add it. The list could help to identify unwanted jobs that regularly wake up your harddisk(s).

Default Time
Job
Explanation
0 4 * * *
/sbin/hwclock -s http://linux.die.net/man/8/hwclock
0 3 * * * /sbin/vs_refresh vs_refresh is for share folder space usage calculation (for Network Share Management)
0 3 * * 0
/etc/init.d/idmap.sh dump related to SAMBA Active Directory configuration. Used if security is set to ADS.
0 3 * * *
/sbin/clean_reset_pwd (unclear) might be the new behaviour of the network recycle bin (purging files after a certain amount of days)
0-59/15 * * * *
/etc/init.d/nss2_dusg.sh is a job of the Surveillance Station
10 15 * * * /usr/bin/power_clean -c 2>/dev/null  ?
4 3 * * 3 /etc/init.d/backup_conf.sh does an automatic backup of several config files in /etc/config.
0 3 * * *
/bin/rm -rf /mnt/HDA_ROOT/twonkymedia/twonkymedia.db/cache/*
Will clear the Twonky media cache
5 0 * * 1
/etc/init.d/antivirus.sh scan 1
If Antivirus is enabled, this will scan the files for viruses
0 0 * * *
/etc/init.d/antivirus.sh archive_log
If Antivirus report jobs are enabled
0 0 */1 * *
/etc/init.d/antivirus.sh update_db
If Antivirus is enabled, this will check  clamav.net for updates

/etc/init.d/startup
If a restart/powerof job is configured in power management

/etc/init.d/poweroff
If a restart/powerof job is configured in power management


Adding entries at the command-line

Here are a couple of examples that append new entries to the crontab file:

echo "1 4 * * * /share/custom/scripts/custom1.sh" >> /etc/config/crontab
echo "40 5 * * * /share/custom/scripts/custom2.sh" >> /etc/config/crontab


Modifying entries

Do NOT edit crontab the usual way!

On a desktop or server distribution, you would edit a user's crontab with:

crontab -e

However, due to the way the QNAP firmware updates crontab, it will be overwritten on the next reboot. Obviously, you want your automation to survive reboots, so edit the crontab file directly with your text editor:

vi /etc/config/crontab

or

nano /etc/config/crontab


Restart the daemon

When you're done, reload the crontab file and restart the cron daemon:

crontab /etc/config/crontab && /etc/init.d/crond.sh restart


Notes

Don't forget to make your scripts executable! Otherwise they will silently fail! You tested your script, right?

chmod +x filename.sh


These instructions have been tested on various versions of QNAP firmware from 3.6.0 onwards.