Tracking server caches

AR System server uses a caching system based on a technology called ehcache. This is a transactional system and allows for granular updates to the cached metadata without the full copy cache operations that were used in earlier versions.

In a server group, each server uses the Java Messaging System to exchange messages about cache updates with other members of the group. By default ehcache uses port 40001 for this service; this is separate to the JMS system running on port 61617 which is used for other server group related messaging.

Use the following configuration ports to set the values:

• Peer-listener-port — 40001
• Cache Peer Remote Port — 40002
• Default-messaging-port — 61617

For more information, see 2024-07-10_01-44-14_Setting ports and RPC numbers.

To enable encache logging

1. Edit the logback_server.xml file by using ConfigMaps. For more information, see the topic Using ConfigMaps to access the configuration files.

   Replace the following entry:

    <logger name="net.sf.ehcache.distribution" level="warn"
          additivity="false">
          <appender-ref ref="ServerGroupLog" />
          <appender-ref ref="AlwaysOnLog" />
          <appender-ref ref="ServerGroupLogToForm" />
      </logger>

   Replace the level value of warn with debug

   <logger name="net.sf.ehcache.distribution" level="debug"
          additivity="false">
          <appender-ref ref="ServerGroupLog" />
          <appender-ref ref="AlwaysOnLog" />
          <appender-ref ref="ServerGroupLogToForm" />
      </logger>
2. Open AR System Administration > Server Information form > Log Files tab.
3. Enable the Server Group Log.
4. Check the Reload Log Conf File check box.
5. Click the OK or Apply button.
   

This enables the server group related ehcache operations to the server group log file. For more information, see the Knowledge Article 000218958.