Jackrabbit Sharing

Web Space Server uses Jackrabbit from Apache as its JSR-170 compliant document repository. By default, Jackrabbit is configured to store the documents on the local file system upon which Liferay is installed, in the Glassfish home/domains/domain1/webspace/jackrabbit folder. Inside this folder is Jackrabbit's configuration file, called repository.xml.

To simply move the default repository location to a shared folder, you do not need to edit Jackrabbit's configuration file. Instead, find the section in portal.properties labeled JCR and copy/paste that section into your portal-ext.properties file. One of the properties, by default, is the following:

jcr.jackrabbit.repository.root=${resource.repositories.root}/jackrabbit

Change this property to point to a shared folder that all of the nodes can see. A new Jackrabbit configuration file is generated in that location.

Note that because of file locking issues, this is not the best way to share Jackrabbit resources. If two people have logged in at the same time uploading content, you could encounter data corruption using this method, and therefore it is not used for a production system. Instead, to enable better data protection, you should redirect Jackrabbit into your database of choice. You can use a database for this purpose. This requires editing Jackrabbit's configuration file.

The default Jackrabbit configuration file has sections commented out for moving the Jackrabbit configuration into the database. This has been done to make it as easy as possible to enable this configuration. To move the Jackrabbit configuration into the database, simply comment out the sections relating to the file system and comment in the sections relating to the database. These by default are configured for a MySQL database. If you are using another database, you will likely need to modify the configuration, as there are changes to the configuration file that are necessary for specific databases. For example, the default configuration uses Jackrabbit's DbFileSystem class to mimic a file system in the database. While this works well in MySQL, it does not work for all databases. For example, if you are using an Oracle database, you will need to modify this to use OracleFileSystem. Please see the Jackrabbit documentation at http://jackrabbit.apache.org for further information.

You will also likely need to modify the JDBC database URLs so that they point to your database. Don't forget to create the database first, and grant the user ID you are specifying in the configuration file access to create, modify, and drop tables.

Once you have configured Jackrabbit to store its repository in a database, the next time you bring up Liferay, the necessary database tables will be created automatically. Jackrabbit, however, does not create indexes on these tables, and so over time this can be a performance penalty. To fix this, you will need to manually go into your database and index the primary key columns for all of the Jackrabbit tables.

All of your Liferay nodes should be configured to use the same Jackrabbit repository in the database. Once that is working, you can create a Jackrabbit cluster (please see the following section).