16.3 Testing Your Lucene High Availability Configuration

When you first set up your high availability Lucene configuration, you can configure Novell Vibe to write Lucene node information to the Tomcat log file so that you can observe the behavior of the Lucene nodes. Then you can take nodes down and bring them up again to see the effect on your Vibe site. This process helps you prepare for the situation where a Lucene node goes down unexpectedly or you need to take one down on purpose, perhaps for maintenance.

NOTE:For background information about the Tomcat log file, see Tomcat Log File in Site Maintenance in the Novell Vibe OnPrem 3.1 Administration Guide.

16.3.1 Configuring Vibe to Log Lucene Node Activity

By default, Vibe writes an error to the Tomcat log file whenever it cannot communicate with a Lucene node. For testing purposes, you can change the logging level so that the Tomcat log file includes a message for each time Vibe contacts a Lucene Index Server.

After observing and understanding the behavior, you should return the logging to normal levels.

  1. Open the log4j.properties file in a text editor.

    The location of the log4j.properties file varies by platform.

    Linux:

    /opt/novell/teaming/apache-tomcat/webapps/ssf/WEB-INF
    

    Windows:

    c:\Program Files\Novell\Teaming\apache-tomcat\
                                             webapps\ssf\WEB-INF
    
  2. Search for the following line:

    #log4j.category.com.novell.teaming.search=DEBUG
    
  3. Remove the pound sign (#) from the beginning of the line to activate the DEBUG logging level for the Lucene Index Server.

    The DEBUG logging level adds a message for each time Vibe contacts a Lucene Index.

  4. Save the log4j.properties file, then exit the text editor.

  5. Stop Vibe, then start Vibe to put the new logging level into effect.

16.3.2 Observing Lucene Node Activity

After changing the Vibe logging level to include Lucene node activity, you can monitor the Tomcat log file to see which Lucene nodes Vibe is contacting.

  1. Change to the directory where the Tomcat log file is located.

    For background information about the Tomcat log file, see Tomcat Log File in Site Maintenance in the Novell Vibe OnPrem 3.1 Administration Guide.

  2. On Linux, use the tail command to monitor the end of the Tomcat log file.

    tail -f catalina.out

    or

    On Windows, download an equivalent command from the Internet in order to perform the following steps.

    For example, there is a command available at SourceForge.net.

  3. Perform some activities on the Vibe site to create new content.

    For example, you could create a blog entry. The Tomcat log file shows that Vibe is contacting each available Lucene Index Server in turn as it submits the new information for indexing. Nodes are considered available if they are marked Read and Write in the User Mode Access box on the Lucene Nodes page.

  4. Bring down one of the Lucene nodes.

    For example, you might reboot the Lucene server, stop the Lucene Index Server on the node, or otherwise prevent Vibe from contacting the Lucene node.

  5. Observe that the Tomcat log file displays an error when the Lucene node becomes unavailable.

  6. Perform some additional activities on the Vibe site that create new content.

    You might notice a pause as Vibe tries to connect with the Lucene node that is no longer available.

  7. Observe that the Tomcat log file shows when normal Vibe processing has resumed without access to the unavailable Lucene node.

  8. Make the unavailable Lucene node available again.

  9. Observe that the Tomcat log file indicates that Vibe has created a journal record on the Lucene node that was temporarily unavailable.

    The journal record contains the indexing operations that failed to take place while the Lucene node was unavailable. Even though the Lucene node is back up, Vibe does not start accessing it until it has been synchronized with the latest index information.

  10. To synchronize the out-of-date Lucene node, follow the steps in Section 16.4, Synchronizing a High Availability Lucene Configuration.

    After the out-of-date Lucene node has been synchronized, Vibe starts accessing it again.

If a situation arises where no Lucene node is marked Read and Write in the User Mode Access box on the Lucene Nodes page, Vibe temporarily accesses the first node in the list that is set to Write Only. If no nodes are set to Write Only or Read and Write, Vibe temporarily access the first node in the list, even though it is set to No Access. This functionality is required because you cannot log in to the Vibe site without access to a Lucene Index Server.