Get Schema from SQLite DB

In SQLite, schemas are stored in the table SQLITE_MASTER. You can easily retrieve it with a command like:

echo ".schema" | sqlite3 ~/.liferea_1.4/liferea.db >> liferea.sql

How to set the timezone on Ubuntu Server

You can check your current timezone by just running

$ date
Mon Sep 3 18:03:04 WEST 2012

Or checking the timezone file with:

$ cat /etc/timezone
Europe/Lisbon

So to change it just run

$ sudo dpkg-reconfigure tzdata
And follow on screen instructions. Easy.

Also be sure to restart cron as it won’t pick up the timezone change and will still be running on UTC.

$ /etc/init.d/cron stop
$ /etc/init.d/cron start

you might also want to install ntp to keep the correct time:

aptitude install ntp

Anti-Spam Email server

In this post I'll show you how to install an anti-spam smart host relay server, based on Ubuntu 12.04 LTS, that will include:

Postfix w/Bayesian Filtering and Anti-Backscatter (Relay Recipients via look-ahead), Apache2, Mysql, Dnsmasq, MailScanner (Spamassassin, ClamAV, Pyzor, Razor, DCC-Client), Baruwa, SPF Checks, FuzzyOcr, Sanesecurity Signatures, PostGrey, KAM, Scamnailer, FireHOL (Iptables Firewall) and Relay Recipients Script.

Continue reading for the instructions.

Changing the Alfresco Site Manage Permissions Action

To change the behavior of the Manage Permissions action to be the same as that available from the Share Repository button.

In:

/opt/alfresco/tomcat/webapps/share/WEB-INF/classes/alfresco/share-documentlibrary-config.xml

Replace:

<!-- Manage permissions (site roles) -->
<action id="document-manage-site-permissions" type="javascript" icon="document-manage-permissions" label="actions.document.manage-permissions">
<param name="function">onActionManagePermissions</param>
<permissions>
<permission allow="true">ChangePermissions</permission>
</permissions>
<evaluator>evaluator.doclib.action.siteBased</evaluator>
</action>

With:

<!-- Manage permissions (site roles) -->
<action id="document-manage-site-permissions" type="pagelink" icon="document-manage-permissions" label="actions.document.manage-permissions">
<param name="page">manage-permissions?nodeRef={node.nodeRef}</param>
<permissions>
<permission allow="true">ChangePermissions</permission>
</permissions>
<evaluator>evaluator.doclib.action.siteBased</evaluator>
</action>

Reload Alfresco and you should now have the more granular permissions from the Alfresco Share repository browser in the Site Document Library browser.

Hide Alfresco Share Repository Browser button

To hide the repository link from non-admin users

open this file:

/opt/alfresco/tomcat/webapps/share/WEB-INF/classes/alfresco/share-config.xml

find this line within the <header> tags

<item type="link" id="repository" condition="conditionRepositoryRootNode">/repository</item>

Change it to:

<item type="link" id="repository" permission="admin" condition="conditionRepositoryRootNode">/repository</item>

Reload Alfresco. Now only admin users will see that link.
Note that the url will still be accessible, this will only hide the link button.

Show the 20 most CPU/Memory hungry processes

Display the top 20 running processes - sorted by memory usage
ps returns all running processes which are then sorted by the 4th field in numerical order and the top 20 are sent to STDOUT.

ps aux | sort -nk +4 | tail -20

Show the 20 most CPU/Memory hungry processes
This command will show the 20 processes using the most CPU time (hungriest at the bottom).

ps aux | sort -nk +3 | tail -20

Or, run both:

echo "CPU:" && ps aux | sort -nk +3 | tail -20 && echo "Memory:" && ps aux | sort -nk +4 | tail -20

Deploying Alfresco To Apache Server

This guide will detail a setup to deploy Alfresco Share to a live server using Tomcat and Apache with mod_jk and mod_ssl it also covers the deployment of the Alfresco's SharePoint interface using Apache with mod_proxy.

Setting up Tomcat

First let's set up a default context so there's no prefix path visible in the URL for Alfresco share. The proper way to do this is by creating the file $CATALINA_BASE/conf/[enginename]/[hostname]/ROOT.xml. When Tomcat is located at /opt/alfresco/tomcat/ the full path will be /opt/alfresco/tomcat/conf/Catalina/localhost/ROOT.xml. Create the following XML document inside the file:

<?xml version="1.0" encoding="UTF-8"?>
<Context path="" docBase="share.war">
</Context>

The path attribute sets the context used in the URL. Using "" as the path thus means 'use as default'. The docBase attribute sets where the real webapp is. When using Alfresco Share this is share.war by default, it's not necessary to use the absolute path.
Now if you restart Tomcat you should be able to reach Alfresco Share at [host]:[port], without specifying the share prefix.
Next we need to setup a connector for Apache. It's possible this is already done on your Tomcat install by default, if not add the following in the Catalina Service section in $CATALINA_BASE/conf/server.xml:

...
<Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />
...

Restart Tomcat again for the connector to be available.

Setting up Apache

If you haven't done already, install mod_jk (libapache2-mod-jk in Ubuntu).
First we define the workers, I used $CATALINA_BASE/conf/workers.properties as configuration file:

worker.list=tomcat
worker.tomcat.port=8009
worker.tomcat.host=localhost
worker.tomcat.type=ajp13
worker.tomcat.lbfactor=1

The name tomcat is arbitrary, so you can replace all occurrences with whatever you like.
Next point Apache to this configuration file. You can either edit your httpd.conf, or if you're using a distribution with a config dir setup (for example, /etc/apache2/conf.d/ in Ubuntu) create a file and add the following content:

JkWorkersFile /opt/alfresco/tomcat/conf/workers.properties

Remember to use your own $CATALINA_BASE if it's not /opt/alfresco/tomcat/.
Finally, setup a virtualhost that will connect to Tomcat:

<VirtualHost *:80>
ServerName share.host.name
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteRule ^/(.*) https://share.host.name/$1 [R=301,L]
</VirtualHost>
<VirtualHost *:443>
ServerName share.host.name
JkMount /* tomcat
SSLEngine on
SSLCertificateKeyFile /etc/ssl/private/certificate.pem
SSLCertificateFile /etc/ssl/private/certificate.crt
SSLCACertificateFile /etc/ssl/private/authority.crt
SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown \
downgrade-1.0 force-response-1.0
</VirtualHost>

This will create a virtualhost at share.host.name (replace this with your (sub)domain location), will force port 80/http to be redirected to port 443/https (forces the secure connection, the 301 will tell the browser it's a permanent redirect) and will serve all content (/*) using the worker tomcat as specified in our workers file (if you changed the name there, also change it here). Be sure to enter your own certificate information instead of what I entered.
You can extend this configuration file in the same way you'd normally do with Apache, so you can add rewrite rules etc..
Restart Apache for the configuration to have effect.

You now have Alfresco Share on a user friendly location, with a user friendly and secure setup. If Alfresco explorer is deployed on the same Tomcat instance, you can reach it at https://[host]/alfresco. Your other webapps should also still be reachable at their context path.

If you want to do the same with Alfresco with the SharePoint Protocol you'll have to set up another vhost in Apache, in this case we will use mod_proxy, like this:

<VirtualHost *:80>
ServerName sharepoint.host.name
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteRule ^/(.*) https://sharepoint.host.name/$1 [R=301,L]
</VirtualHost>
<VirtualHost *:443>
ServerName sharepoint.host.name
SSLEngine on
SSLCertificateKeyFile /etc/apache2/ssl/sharepoint.key
SSLCertificateFile /etc/apache2/ssl/sharepoint.crt
SSLCACertificateFile /etc/apache2/ssl/sharepoint.crt
SSLProxyEngine On
ProxyPass / http://localhost:7070/
ProxyPassReverse / http://localhost:7070/
ProxyPass /alfresco/ http://localhost:7070/alfresco/
ProxyPassReverse /alfresco/ http://localhost:7070/alfresco/
ProxyPass /share/ http://localhost:7070/share/
ProxyPassReverse /share/ http://localhost:7070/share/
ProxyPass /_vti_bin/ http://localhost:7070/_vti_bin/
ProxyPassReverse /_vti_bin/ http://localhost:7070/_vti_bin/
ProxyPass /_vti_inf.html http://localhost:7070/_vti_inf.html
ProxyPassReverse /_vti_inf.html http://localhost:7070/_vti_inf.html
ProxyPass /_vti_history/ http://localhost:7070/_vti_history/
ProxyPassReverse /_vti_history/ http://localhost:7070/_vti_history/
#RewriteCond %{SERVER_PORT} !443
#RewriteRule ^(.*)$ https://sharepoint.host.name/$1 [R,L]
SetEnvIf User-Agent ".*MSIE.*" \
nokeepalive ssl-unclean-shutdown \
downgrade-1.0 force-response-1.0
</VirtualHost>

Finally, on your Alfresco's global.properties file you'll have to set the following variables:

vti.server.external.host=sharepoint.host.name
vti.server.external.port=443
vti.server.external.protocol=https

so that your Edit Online links are generated correctly.